The Rectangle Project: http://www.rectangle6x9.org/
And one that's a Yahoo group: Camp Square Crew. We're knitting squares to be made into afghans for the Victory Junction Gang Camp. (http://www.victoryjunction.org/aa_home/index.html
for more about the camp) I actually had a LYS owner give me a 10% discount on the yarn I bought today b/c I was using it for this!