I haven't been able to find a phone in use coincedent with the laptop's fuzzing out. There is a neighbour with a Belkin54g that I sometimes see listed, but it's a really low signal. I've switched channels away from him. I'm now on 11. Could it be that his ap is bouncing around the spectrum and only sometimes causing interference?

I suspect the Belkin is running out of the box settings, without any security. Mine's about as tightly locked down as I know to make it. (wep and mac filtering both on)