I think you should join a local quilt guild or club. You'll find they probably donate to charitable causes, and may discover what you want to do with your tops. As an added bonus, you'll make wonderful new friends who share your passion.
One other place a completed quilt can be donated to is a women's shelter. Our guild is getting ready to finish a top someone donated to us, and that's where it will go. Just another great cause which I believe hasn't been mentioned yet.
God bless!