I still use it on my older XP machine and there are really some pretty spectacular desktops themes that people have created. One particular I am presently using looks like the inside of a spaceship. When you open folders, the windows are countoured with a top of details that would be pretty hard to produce in WIN7 without "External" help. My task bar is also contoured and moulded in appearance. Again, it doesn't add ANY productivity to the PC but it's just fun to screw around with the various desktops and themes.
By the way, the reason I have not uptated this particular machine to 7 unlike all my other PCs is because I use AVID Liquid Edition for my video editing and it has not worked under the 7 platform. It is only XP certified. It can half way work under Vista if compatabilty mode is used during the install. However it will totally crap out under Win 7 which is really too bad. But that's another subject!