The Zebra Midge is a great pattern:
http://www.swedneckflyfishing.com/zebramidge_steps.htm
Al’s Rat is simple and fishes well:
http://www.littlelehighflyshop.com/Flies.aspx#Als_Rat
A small Brassie using fine wire instead of thread for the body can be killer in red, copper, black, or green:
http://hipwader.com/2003/red-brassie-midge-pattern
Good luck.