It might not seem like the most personal present, but you can't argue with the ease of gift cards--all it takes is a trip to just about any corner store. You can throw a buddy some iTunes bucks or points toward a game console's online store (at this point a ton of great games lurk on Xbox Live, Sony's PSN Store, and Nintendo's WiiWare channel). Those in a hurry can purchase and print up a gift certificate at places such as Amazon.com, or give the gift of Netflix subscriptions.
If you've got time to run out to either Target or Best Buy, you can grab the most surreal gift cards around--MP3 player and digicam gift cards. They are technically gifts unto themselves!
Or, for all you cheapskates out there, you can do what I do: Hand-draw a coupon good for a year's worth of tech support for the in-laws. Hey, you're gonna wind up doing it, anyhow.