filters, firewalls, clogged networks, cheap parts, old technology....need i say more?  why is this even being discussed?  

As I sit here at work on lunch, on a buggy 2,25 year old dell

 XP and IE6. IE6 does not render pages correctily anymore, IE freezes up routinely.  IT tried to install IE7 and it caused a complication

 that required they dump it ans stick with 6. I know the feeling.

I've been asking this same question. It seems that every university I have been to stocks up on about 200 Dell machines. They must get some ridiculous discount, because no one in their right might would purchase these things otherwise. They take about 5 minutes to log on, and then another 5 or so just to load all login items they have set, and even then the computer is barely functional. 

 Im not saying this is an issue with Dell, Im saying schools and workplaces need to step it up and buy some functional machines. Actually, it probably is Dell's fault. If they didn't offer such garbage, the schools wouldn't have the option of buying them.

From my own experience, taking machines from work that are old and slower than anything and reinstalling the OS on them makes them rather useable. I don't mean just the refresh of the OS, but from removing all the corprate level anti-virus and other 'baseic image' software makes the machine have some life.

Currently I'm typing on a thinkpad T40 that was thrown out by my compan's tech team because "it was too slow to be useable". After reinstalling the OS, and a year of normal house use, its still quick and productive.

I really don't know what they do to the machines, but what ever it is, I don't blame the hardware.

My guess is the work machines are allot older than the two year old imac. 

Just a guess. 

This morning my computer took 17 minutes to boot up and start being responsive. It is a 2005 custom built from the bargain bin workstation. How do I make the case for upgrade? The macbook + 24" monitor I want is over $2400.

The company uses timekeeping softward that works on Vista but was was hasn't been upgraded since 2002. (If the company starts replacing these bargain bin workstations, it should update it Office and timekeeping packages as well.) My day would be better on a macbook pro or a decent W7 machine. But would I be more profitable? I need a way to make the case.

Does anyone else end up doing work at home just because the work computer can't handle it? OmniGraffle on my Core (1) Mini is a dream compared to making a diagram in Office 2002.

Yeah, no kidding! 

My work compy is a Mac Pro running Leopard, but at home, I have an MBP running SNOW Leopard! 

Using my computer at work is like being forced to go back in time to, like, JULY, man! 

The answer to this question is simple, and in large part answered by the first poster "filters, firewalls, clogged networks, cheap parts, old technology".  The Why's of that answer are a bit more complicated, but as an IT Professional I'd like to take a stab at it:

1.  Most average users in today’s corporate environment are IDIOTS.  I mean seriously, very few have a clue how to open an application without a special icon on the desktop.  Obviously most of the readership here will be the exception to that rule.  I am lucky if 85% of my users can tell the difference between the monitor and the PC when I ask them to power off the machine, much less concepts like DHCP and DNS...

A.  This causes the need for a managed environment in an effort to stem viruses, spyware, adware and other such garbage from being installed.

B.  Additionally, the complete lack of computer skills requires significant hand holding.  You have to map all the drives, create shortcuts to necessary resources, map printers, and on mobile machines encrypt drives.  This is necessary because the technical level of the average user is slow low, if it's not spoon fed to them, they are simply lost.

2.  Last but not least, there is significant capitol involved in the technology investment of a corporation.  It is simply not feasible for most companies to upgrade every machine for every user every 3 years.  I am lucky as I work in health care and we are often forced into an aggressive refresh cycle as many of our systems can ultimately affect patient care.  Even still, many office machines and lower priority areas are forced to wait until a workstation dies a natural death prior to an upgrade, which may well end up being a hand-me-down from a more critical unit.

I'd like to close by stating I have run into very few counterparts that enjoy being the "IT Nazi".  Past experience, and complete lack of technical skill by a majority of users, creates a situation where excessive startup scripts, security, encryption, firewalls, filters and authentication are necessary evils to protect what performance we can provide.  I'd love to put a brand new machine on every desk every year, completely unlocked and open, with any and every tool a user might need, unfortunately this is unrealistic.  It is cost prohibitive for both hardware and software.  It additionally provides no security for the data on our network; provides no protection for the network bandwidth (streaming music, and video would abound); and those poor machines that are so slow now would be even worse with browser conflicts, 8 different search toolbars, spyware, adware, and viruses...

I understand the question, and even the basis for complaint, however, I feel the situation is justified in most cases.

I work from home the majority of the time and I always end up using my Mac Mini (on a 40" 1080p) or my MacBook Pro 15".  They don't crash.  It really comes down to that.  They don't crash.

My work PC is an HP 8510p.  The fan goes near 100% almost constantly, even when it's sitting there idle.  That's annoying enough.  The hard drive has physically crashed 4 times in the 18 months I've had this laptop.  My 2004 iBook hasn't physically failed once, nor have any of my other Macs.  Why?  At least in the newer models and older Pro models it's because of the motion sensor.

At grad school everyone except me has a PC.  To log onto the school network takes forever because it's constantly updating the Cisco Clean Access nonsense.  My MBP takes but a second to log on.

The solution is quite simple.  Move to more web-based apps whenever possible.  You don't need a fat client for a CRM or bug tracking tool.  Perhaps more importantly, don't use software that only works with IE!  That's not true web software.

Google Docs does most of my Office needs, including collaboration.  Google will eventually defeat MS if they continue their antiquated thick-client OS-specific software. (Office on the Mac isn't the same).

Web-based can be centrally managed and secured regardless of the client (PC/Mac/dumb terminal/phone/etc).

What's sad, is that my computer is fairly new.  We got them last year.  It has a pentium dual-core 2.4 GHz processor, with 1GB of RAM (not terrible for a high school).  It came with Vista on it (I'm assuming because of the sticker), but we're still being forced to use XP. 

The sad thing is that I graduated from the same high school that I'm now teaching at (that's not the sad part.... maybe...) and when I graduated the computer science class I was in had upgraded all the computers  to XP, and now that I'm teaching here 7 years later, we're still using it. 

I work for a Google partner company doing large scale Google Apps implementations for big enterprise. The $$ saved from the EOL of on premise Exchange and Notes mail stores is so big (1/5 the cost), that most big IT shops find they have extra cash for decent PCs and a shorter refresh cycle. Not to mention how much faster old hw runs when not having to load up feature bloated, piggy client apps just to do mail and calendaring. Use a modern browser, get 25GB of mail storage and uninstall that old client crapware. Your PC will thank you...

Why can't my office cube have  a leather couch like the in my living room?  Instead they give me this boring desk chair.  And why is the company car a Toyota Camry when at home I have a Corvette ZR1?

Work and home are two different things, with different needs, different product licensing agreements and different liability and security concerns.  It is always a matter of the right tool for the right place.  A home computer is not the right tool for most businesses, that have a whole set of privacy, security and liability concerns that have to be met. 

Want to do some web surfing during lunch hour?  Buy your own smartphone.  Want to work on business data at work? You better be using your office-issued computer, or you and your employer could be in big trouble.

Am I missing something?  Aren't Macs for people who don't know how to use real computers?  I think there's a reason they have like 3-4% market penetration in the corporate world.

That's why the computers are so slow.  As pointed out above, they need to have everything done for them, map a network drive, map a printer, have to have a special icon in front of thier face etc.  These machines would destruct themselves in about a week if no firewalls, anti-virus, anti-malware were not installed thus making them snail slow.  And forget about laptops, they routinely slam down thier notebooks while running, drop them, bump them etc.  They don't understand that these are delicate electronic devices and hard disk platters spinning at high speeds with disk heads flying over at minute tolerances.  The slightest bump and CRASH.  Then they wonder why thier laptop all of a sudden doesn't boot up?  idiots.