soscrappy runs a Rainbow Scrap Challenge each year. Each month gets a new color and she is posting a few blocks a month...could be one a week, not sure. This yr, she is making each block the center of a sawtooth star block. I hope to keep up as leader/ender projects as time allows.
http://superscrappy.blogspot.com/
For applique lovers, Erin Russek offers a free applique block of the month. The center is available for purchase, but you can make a nice quilt out of just her blocks as well.
http://erinrussek.typepad.com/one-piece-at-a-time/