I am always fascinated by scrap quilts. I found 2 good ways to use scraps;
1. When you do any project (even if it isn't a quilt), make a block with the leftover pieces. Don't worry if all the blocks aren't the same size - you can always add borders to the smaller blocks. I have already gotten 6 blocks for my nascent sampler quilt by doing this.
2. String piecing makes some beautiful and unusual blocks using scraps.You can even sew small pieces of fabric together to make a 'string' and really end up with some cool patterns.
If you can't tell, I have a LOT of scraps!