After posting my Cookie Gun diagram and related pics to Flickr it's quickly become among my most popular pics. Thanks to everyone for the nice comments and suggestions. I expect to see lots of better designs and interesting photos to come.

Update: my cookie gun lens fell off its mount. So to all of you out there who are just using tape to hold the mount in, obviously not a good idea. The lens is okay but I've made it a bit more permanent by using Gorilla Glue on it.