One of the ladies from Piece O' Cake (sorry can't remember her name) gave a class and taught us to roll up our binding tape by just folding over the first inch and then rolling up from there. It makes a firm roll and then I just put a pin in it to keep the end from unrolling. I have use that method ever since with all of my scrap strips and I put them in a clear, plastic jar. This method works wonders, as it keeps everything neat, ironed and you can see the colors through the jar. It also is very pleasing to the eye to see a colorful jar sitting on my bookshelf.
For my rectangular, triangular and square-ish type scraps, I keep them flat in a plastic box so that I can see them and I don't have to iron them again when I need to use them for a scrap quilt.