Websurfing in bed
If you install a wireless network in your house, and you own a laptop, be very careful. The combination of wireless internet plus laptop is dangerous because it allows you to websurf in bed. This is just about the most useless of all possible activities, but so easy and comfortable that it is hard to stop. Several times over the past few days I've been trapped by my own laziness and wasted several hours websurfing in bed that I really would have preferred to spend doing something useful.
Let this post be a warning to you all! From now on, I will keep my laptop plugged in in the living room when I'm at home, just to make it harder to do the bed thing.