Here's a very simple eel fly that I've found very effective after dark.
Last season it accounted for 2 bass to 27" in the waning hours of the Martha's Vineyard Catch and Release Tournament (It was a classic - dark and stormy night).
Another notable catch was a 34" bass from an 12 foot hump in 50 feet of water in Narr. Bay.
Basically, it is just an olive rabbit strip attached Matuka style to a yarn body. I use either mono or copper wire to bind the strip to the body.
This is my last one, so it is a little used and ragged.
Threaded Mode