Artist Projects on twitter

I've recently started a small, just for fun project on twitter called "Twittcher".
www.markbrereton.co.uk/twittcher

It's based on overheard conversation in public places. I was thinking that perhaps it could become a collaborative project in some way. People could contribute with images to compliment the text? What do you think? Or perhaps we could start a completely different collaborative project that can be shared across the world wide web.