---

There are several slang names for a foil, eg. Wail Tail, Fin.

There are many versions of the same thing. This is one example.
http://www.wholesalemarine.com/davis-...-tail.html

While trim tabs are effective, they are alot more money, require drilling into the hull under the water line and wiring for electrics or hydraulics.

The other decent option to consider is a 4 bladed lifting prop. They work well but are more expensive than the foil.