Made a bag/quilt for my son. He's only 2 months old right now (can ya tell I'm excited to go camping with him?!), so it should work as a bag for a couple of years, then work as a quilt when it becomes too narrow for bag use. I used 1 yd of 5 oz Climashield from Thru-Hiker and 2 yds of ripstop 2nds from DIY Gear Supply. Sewn footbox, zipper on the side, and shock cord on top for quilt use. 14.0 oz, on the dot. First quilt project, I think it turned out ok! I might follow up and make a 2.5 oz climashield quilt for myself in a few months now that I have an idea of how it works.
Basically followed the ideas from this thread: http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=74053