Ok, so this isn't really a Windows tip, but it is useful none the less. Get (most of) the gunk out of your keyboards with a Post-It note.
If you take your laptop with you everywhere and use it constantly, you're liable to get a build-up of hairs, crumbs, and other detritus in the keyboard. To clean them out, take a Post-It note (the new 'super sticky' kind especially good for this) and run the adhesive edge through the cracks in the keys. I've also found that if you very lightly drag the sticky end of the Post-It note across the screen of your monitor or laptop, it does a great job removing all the dust that's built up on it. (be very careful when doing this-hold the edge of the paper furthest from the sticky edge and apply no pressure)