Been using some of the X-10 stuff lately to control all the vampire electronics I have (no need for all the video game units, etc. to be running all the time - and being able to turn outlets/power strips on and off with my remote makes it worth the effort), and the new apartment has been driving me nuts. One of the controlled outlets would only work sometimes, and would just turn on and not off others. Finally traced it down this morning to the CFL light bulbs in the kitchen. 3 bulbs, 2 of one kind and one of another - when the 2 that are the same are both on, the X-10 outlet in the other room won't respond. Unscrew one of the CFLs, and the outlet works again!

I swear, if it's a weird problem I'll find or encounter it!