I started out using spray on polyurethane and deft. Didn't like them very much, especially in satin. I mostly use danish oil now which is a mixture of polyurethane, denatured alchohol, and boiled linseed oil. It's easy to touch up and refinish later if need be.
Massey finish is killer too, pretty much a mixture of epoxy and acetone. The problem is it's harder to touch up if you get a scratch in it.