Has anybody ever had their dome lights just come on by themselves for no apparent reason?

This has been while driving at night, with the headlights on (switch set in the auto position) for no apparent reason. That is, I haven't noticed it being related to going over a bump, braking, the transmission shifting or anything like that.

Both dome lights (the two lights on either side of the interior rear view mirror) come on at the same time

It is not a huge deal (I can easily turn them back off!) but I'm curious if anyone has had a similar problem and might have any ideas of where to start looking.

Thanks,

Mark