Publisher: Sega

Sega, the arcade game maker, published its own Atari 2600 cartridges in 1983 and 1984. Most of them are home versions of its arcade games, scaled down to fit the console. Buck Rogers: Planet of Zoom, Tac-Scan, Sub-Scan (based on Deep Scan), Congo Bongo and Up’n Down all started out in Sega arcades. Star Trek: Strategic Operations Simulator squeezes a vector arcade game with a panel of buttons onto a one-button joystick. Sega also converted two Bally Midway hits, Tapper and Spy Hunter. Thunderground is a tunnelling game that borrows its idea from the arcade game Borderline. Outside studios did some of the work: Beck-Tech converted Congo Bongo and Tapper.
The site has all ten Sega titles listed here, including the unreleased Ixion prototype. Some places to start:

Spy Hunter (1984): a spy car that turns into a speedboat, played with two joysticks.
Tapper (1984): a bartender keeping four bars supplied, with soda instead of beer.
Star Trek: Strategic Operations Simulator (1983): command the Enterprise against Klingons and NOMAD.
Buck Rogers: Planet of Zoom (1983): a behind-the-ship shooter skimming low over a planet.
Thunderground (1983): dig tunnels towards enemy bases while tanks hunt you.
Ixion: a prototype of a game that was never released.

Pick a game below and play it in your browser.