I got a REALLY simple one from my first fly-tying kit.

Use whatever hook you like, I like a #8 or #10 streamer hook.
Tie on some bead chain (metal for weight or plastic) eyes.
Use olive chenille for the body. I like to tie it in behind the eyes, and wrap it down to the bend and back.
Tie in and wrap a hackle behind the eyes.
Bring the chenille forward through the hackle (preferably on top) and take it between the eyes.
Tie off and clip excess.
Whip finish and cement to taste.

Make sense?

I caught a 4 lb channel cat on a #10 with metal eyes. Very fun.

Lux