So what do you do with old business cards?

I found that after going to a bunch of University degree shows and buying artistic treats on-line I wound up with quite a lot of pretty business cards. I don't need these any more as I have bookmarked all my favourite websites and blogs but what to do with the business cards. They are too pretty to just throw away. 

So I decided to make a collage and pattern out of mine. This way I get to see a lot of really great art from a bunch of artists at the same time. This framed piece sits on my desk at home and it is a source of some really great inspiration from time to time. 

So what do you do with old business cards and art references?