I've seen them used as paths, usually trimmings, but whole pieces should work.

Can you offer them on Craig's List or Freecycle? We were building a shed a couple of months ago, and I tried to collect random shingles (didn't care about color). I couldn't respond fast enough to get them, there seemed to be quite a demand. I think in tight times, people are scavenging. I know we were!

Store them some place. If you have damage to your roof you will have pieces to fix and a sample of the color for future reference. Even with a good roofing job you may find that you find problem areas that need a little TLC.

I had an ice dam build up that tore several shingles and the leftovers helped.

I would save some of them, as maifleur says, in case you need to make a repair.

If after saving you feel you have enough to spare, I second the freecycle or craigslist option, if you have not already tried that route. It's amazing what you can find and/or give away there, and there are always people looking for items like this for home improvement projects.

:)
Dee