I have quiltbuilder, 123quilt, and just ordered quiltpro. I really enjoy mine a lot and use them all the time! I even bought copies of them for my mom! Who needs computer games, I have my quilt desing programs!!!
For those of you asking what they are for, it is a software program that you get to design a quilt on, you can choose your sizes, your blocks (some you can desing your blocks), choose some fabrics and get the sizes to cut, etc...well worth the money (no matter which one you buy) if you like to do your own patterns!
Just for fun, you can go to 123quilt.com and download a free 30 day trial of 123quilt to play with. I don't think you can print with the trial, but it is fun all the same!!!