My desk is next to a huge window, and even with the heat on my hands get really cold. But then I got a heated desk pad / mousepad. I thought it was a gimmick, but I love this thing. In just a few minutes it warms up my hands and wrists and keeps both my keyboard and mouse at cozy temps.
Aw man, slippers are the best part of winter! Maybe you just haven't had nice ones. In addition to the usual furry/fuzzy slippers most people think of, I like to mix it up with "house shoes" (i.e.: shoes but ones that never go outside) like EVA Birkenstocks[0]. They're extremely light and the half-inch insulation they provide from the cooler ground makes a big difference for me.
I used to have a small heater running under my desk but I bought these [1] recently and the heater hasn't been on since. My feet are toasty but don't get hot and sweaty.
