Clocks are on the top of my favourite decoupage items list. The surface is usually flat so it's easy to work on it. Also, there is actually nothing to limit you in choosing style or motifs: you need clocks everywhere: in the kitchen, bedroom or children's room.
Your friends need them too :) So hand-decorated clock would be a great gift idea!
There are some clocks I've made recently. I used decoupage paper and printed tissue napkins.
Time flies - but with decoupage you can stop it for a moment :)