Nearly every quilt I make has scraps leftover from other projects in it. It's almost a matter of pride for me. As my grasp of color theory improves, though, I find myself going for controlled scrappy over "everything but the kitchen sink scrappy" more and more. :)
I love string and crumb quilting, and I'm saving up a bunch of 1.5" squares to use for a postage stamp quilt someday.