The Tate Modern is displaying an retrospective exibition of work by Francis Alÿs from 15th June to 5th September 2010. View details here.
Alÿs is a Belgian-born mixed media artist who lives in Mexico City, experimenting with anything from paint to video. A man pushed a block of ice through Mexico City until it had melted; Alÿs documents these puzzling projects as explorations of himself and his subjects. It's art and poetry amongst politics. I want to go look.