Asteroids Passwords and Easter Eggs (GameBoy Color)

Asteroids has been ported to multiple systems, including many of Atari's systems (Atari 2600, 7800, Atari Lynx) and many others. The 2600 port was the first game to utilize a bank-switched cartridge, doubling available ROM space. A port was in development for the 5200 and advertised as a launch title but never officially released, although an unofficial release was produced by AtariAge. 1993 saw a release for PC's with Windows 3.1 as part of the original Microsoft Arcade package. Also, a new version of Asteroids was developed for PlayStation, Nintendo 64, Windows, and the Game Boy Color in the late 1990s.

A port was also included on Atari's Cosmos system, but the system never saw release. Many of the recent TV Games series of old Atari games have included either the 2600 or arcade versions of Asteroids. Atari has also used the game for its other late '90s and 2000's anthology series. In 2004, Asteroids (both the Atari 2600 port and the arcade original, along with Asteroids Deluxe) were included as part of Atari Anthology for both Xbox and Playstation 2, using Digital Eclipse's emulation technology. (This package was released for the PC a year earlier under the title Atari: 80 Classic Games in One.)

Asteroids was scheduled for release via Xbox Live Arcade for the Xbox 360 on November 28, 2007, with an option for special revamped HD graphics and a high-speed "throttle monkey" mode. (Wikipedia)

Passwords

Level codes
SPACEVAC - Level 02

STARSBRN - Level 03

WORMSIGN - Level 04

INCOMING - Level 05

Others
CHEATONX - Cheat menu

QRTREATR - Play Classic Asteroids

PROJECTX - Unlocks Excalibur ship

Easter Eggs

Classic
To unlock classic mode shoot 2 of the white, 2D asteroids and go to the main menu. Must do this every time you turn game off.

Here's a neat fan video showing the best games of the last 30 years, including Asteroids: