Do you like a treasure hunt?

If you're in the USA or London, you may want to try Wikipedia Loves Art.

It's a research project disguised as a game.

You take you camera to 15 selected cultural institutions in the USA and London, take public domain photographs of selected works of art, post them on Flickr and "win".

There are also associated meet-ups for the socially inclined, and individual competitions in some of the participating institutions.

Read about it here.

Or here.