[ferretchucker]

This'll be funny if you pull it off. You want to be careful he doesn't realize there's a human messing with him and attack you. Also, hope he's up for a laugh.

-Find a radio station before hand which plays old music. Tune the radio to that very quietly then turn it up while he's downstairs.

-Get an identical TV remote to his and mess with it.

-Light a cigarette/pipe/cigar and let the smell fill the house.

-(very subtle) flick the corner of a rug so it looks like somebody has walked over it.