My first quilt was a Penrose quilt, and it's big enough to sleep under, maybe 5 feet long. The top is in silk and the back is flannel, and i hand sewed most of it, including the quilting. It's starting to show some serious wear, so it's not really in good condition to be photographed or displayed. But, it keeps me warm at night and hides my ugly comforter underneath it.
After I learned more about quilting, I found that the Penrose tilings are about as difficult of a pattern that one could quilt. So, most of my subsequent quilts used easier designs to sew, just for practical purposes. It pays time-wise to work with the medium rather than against it.
I've done several other quilts in various sizes ranging from pot holders to queen sized (the technique is the same). You can see a couple of my more recent quilts (that I'm particularly proud of) here:
http://curvebank.calstatela.edu/quilt/quilt.htm
If you scroll to the bottom, you can see how large they are (and a couple of goofy pictures of me explaining them).
Thanks for your interest Alex.