The Sketchbook Project looks like a fun idea.
Participants pay $25 to receive a blank Moleskine Cahier sketchbook, which they complete after choosing from a list of themes and send back. The completed sketchbooks will then be exhibited at museums and galleries on a tour around the country. After touring, the sketchbooks will become a part of the permanent collection at the Brooklyn Art Library and will be open to public viewing.
I wish the price were a bit lower (after paying the $25, participants have to pay another $20 to have their work held in the permanent digital collection) so that this felt more like true "public art" by and for the people, but a good idea nonetheless.
(Example sketchbook by Katie Castelli)