I am planning on making more of these pants using some vintage patterns that I have been collecting. These particular style is featured on the November '09 Vogue issue.
Here are my spring harem "hammer" style pants.
I used McCall's M5858 pattern
Pattern M5889 is from the new McCall's collection. These look very easy to make and are ideal if you don't dare to wear the harem pants with the "pouch" down there.