Sub Diver is a delightful Ludum Dare 29 entry (Unity, in-browser) where you direct an underwater craft around to pick up cargo, and deliver it to the sea base beneath the waves.

The controls are WASD or arrow key based and simple to pick up. You just rotate the sub until it's pointing the direction you want, then press up to get it moving in that direction. Navigating around rocks, past exploding mines and toward your haul is fun, though a big drain on your fuel reserves, so it's important to scoop up any canisters you see around as well.