Huge chalk messages

From Purdue CIA

We lay out a huge grid of 10*10. Each square is 4ft by 4ft. Each person either draws a portion of a larger image, or their own image entirely. The first would create an enormous image. The second would create a quilt.

Do this at 2am in the middle of busy intersections. Each letter could be 10 feet tall.

[edit] Ideas for messages

1. Reclaim public space

2. Our existence is mysterious

3. Noone knows why we exist

4. Talk to strangers

5. Live deliberately

6. Don't be a slave to pants