I am so excited to see this blog post by Urban Threads (the makers of the coolest embroidery designs, ever!) http://www.urbanthreads.com/blog/?p=7487
Anyway, basically they are giving away a free pattern for a bunny (see below)
You stitch them up and print out the little paper that goes with them and leave them around for people to find. Such a cute idea! You can even track them if you find one on the site.