I've wonder the same thing. I've never used them.

I use charm packs all the time. I am working on a dresdan plate using charm packs purchased from Missouri Quilting and using their video tutorial as a guide. It is so easy so far.

I've done a bowtie quilt with charm packs. Each charm makes one bowtie with just a tiny bit of waste and it allowed me to have many more fabrics than I would have otherwise.

I have the 1930's repro charms that I plan to do a dresden plate with soon.

There are lots of ideas on the Moda Bakeshop website.....

http://www.modabakeshop.com/

I've made regular quilt tops using just strips and recently I used the pattern "Strip Search" to make a Halloween quilt. Charm packs are useful for table runners because you have a variety of beautiful fabrics.

I've done 3 quilt tops with jelly rolls. One was from a magazine pattern that was made for a jelly roll. One was the boxy stars pattern at quiltville (it was a quilt along) and one was a non jelly roll pattern from a magazine that I worked up in Electric Quilt to use a jelly roll.

I have made several quilt tops with charm packs, jelly rolls and turnovers and one with a layer cake. I love to use the charm packs and make tumbler quilts. And 4 patch and 9 patch are perfect for charms. I have used turnovers to make pinwheel quilts. I have a Mary Englebright pinwheel ready to be put together. The honeybuns don't seem to go as far in a quilt top, more like a small lap size quilt. I made a hexagon quilt top from a layer cake that needs to be quilted someday.

I love the ideas that they offer but since I have the time right now I prefer to choose my own style of fabric and to cut my own , its so much more cost effective.
If I had unlimited funds and no time I probably would buy some of them.