On my odd days off I like to visit friends, which is really the only way I can escape geekdom, if I don't get out of the house I end up in front of the PC. Nice long bar lunches are a great way to spend a day off, maybe not so fun if you have work the next day. I usually prefer to take long weekends (Friday and Monday off) than a whole week, I'd much rather have 3 long weekends than a week off - damn I miss bank holidays!.
When I have a week or so off, I often watch a lot of movies, once I had a week off before the 2nd series of LOST, so I spent the whole week watching season 1. That's pretty geeky, but it's certainly something to do, beats staring into the abyss, dreading the inevitable return to work.
I do sometimes write the odd tech demo when on holiday, but like IanM I prefer not to work on proper projects, even though it is a hobby I spend a vast amount of time on, it is good to take a break from serious coding altogether. Last time I think it was that weird crystal worm demo, there's nothing better than a totally simple, organic concept that looks pretty to keep you occupied.
