Well, my desktop, unfortunately, has been relegated to making finite element runs. Its a shame when you can't use your computer for five days because its tied up completely by a run. EVERY now and then, I'll sit down and encode the CDs I've bought since I last did a batch (having an MP3 stereo in my car is nice--but the task of encoding all of your CDs and filling out the ID tags isn't exactly fun).
My newly acquired laptop is basically used for everything--web, office apps, looking up journals/books in the library, even post-processing the FE runs.
I do no gaming (my GC does that if I want to--and I seldom have time to).