Here is a useful explanation of all the pre-cut packs, like charm packs and jelly rolls: http://www.modabakeshop.com/p/bakery.html
You can also find some interesting patterns on this site to use the charm packs.
I like charm packs because I'm a novice quilter - I'm capable in the construction but I am not all that great on fussy quilt patterns (I just don't have the patience to cut all those tiny little bits!). Often I will use charm packs to make an old style patchwork quilt, just sewing all squares together with a nice contrasting border and trim, then quilting by stitching in the ditch. These quilts come together super quickly and always look pretty, even if more experienced quilters might scoff at my laziness!
I also just use quilting cotton for backing and between the squares, if I'm doing such a thing. Keeps it all more uniform, rather than using homespun where the quality varies somewhat. I have used homespun for the backing, though, but I prefer to buy backing from a quilt shop (which is basically quilting cotton in larger widths) to keep my fabric type the same. Initially you don't really notice if you use different fabrics, but once you throw the quilts in the wash a few times they can wear differently and you can notice a difference).