No they don't smell, but they do make a low level humming noise. I've just upgraded from an iBook G4 to a MacBook (white with superdrive). The only downside I've noticed so far to upgrading is that I have my notebook connected to an external amplifier and set of speakers. If the MacBook is plugged into the mains all is fine but if I unplug it to let the battery drain, I find that my external speakers give off a low level hum which is really annoying! As soon as I plug the power adapter back into my MacBook, it goes away. It never did this on my iBook, or the Dell 6400 inspiron I had. Any ideas?