That's a tough one--at least it would be for me. I understand the value in stretching outside your comfort zone when it comes to fabric choices, and I have branched out over time, but my primary concern about swapping with others is that I would end up with a whole lot of stuff I didn't like. Lots of quilt shops have bins or baggies with scraps in them, allowing you to pick and choose, that might be a place to start.