Check out Bonnie Hunter at
http://www.quiltville.com She has all kinds & sizes of scraps she manages to make use of.
http://www.quiltville.com/
Personally, my size limit minimum is 2x2" for log cabin centers. I sort mine by color in ziplocs. When making swap blocks, I always go through the scraps first. Then I'll dig into fat quarters. Background fabrics are my only exception to my "swap rules" but even for that I prefer to dig through my stash of remnant bin treasures rather than use yardage if it's for swap blocks.