The Fibonacci Felted Bag was created by Brynne Sutton, and is available on her website, All This By Hand. It's a fairly small bag made out of Nashua Creative Focus Chunky (only two balls are needed). I've currently got a washcloth project in it, and I'm enjoying finally using one of my own creations for something useful! My bag measures about 10.5 inches wide by 7.0 inches tall, and is about 3 inches deep at the base.
The other felted bag is the Slouch Bag, available at The Knitting Zone. There are quite a few fun felted bag patterns there, too!
I'm hoping to make a bag with flowers - yikes, intarsia.... but I'm imagining a really beautiful brown bag with blues, purples, pinks, and greens....haha.