It's a nice way to get points, especially spiky points like for the wild quilt below. I personally find it a bit messy and tedious, and it's not fabric-efficient, but you can get some REALLY nice blocks made that way. It's good for group projects, too, so the blocks all end up the same size. I don't often do it for entire quilts, but sometimes I will use that technique for certain parts of a quilt. Sometimes I use the fabric itself as a foundation instead of paper, like in the Tennesee Waltz quilt. Those spiky points are originally rectangles sewn to lines on the background fabric and folded over to make the triangles (Instead of cutting triangles). I trim away the excess seam allowance from behind. The rest of the quilt was pieced with regular methods. I find the pineapple quilt easier to sew on a foundation, too!
Pineapple
[ATTACH=CONFIG]4416[/ATTACH]
Tennessee Waltz
[ATTACH=CONFIG]4819[/ATTACH]
Spikes
[ATTACH=CONFIG]6521[/ATTACH]