I use Danish oil on my workbench. It helps keep the surface relatively clean, it's a penetrating finish, so it should harden within the wood rather than just on top. That said I can't really say it's very protective. I generally sand down my bench top and reapply a few coats every once in a while.
It is basically linseed oil with varnish. Usually 3 to 1.
What are you looking to get out of a finish?