Austrian Norbert Kehrer reproduced the highly successful MAME arcade game emulator, written entirely as Java applets. His objective was to allow any web browser supporting Java to run these games without the need for downloadable plugins.
39 Emulated games as of March 2002:

• Joust (Williams 1982)
• Defender (Williams 1980)
• Tetris (Atari Games 1988)
• Carnival (Sega 1980)
• Berzerk (Stern 1980)
• Tempest (Atari 1980)
• Arkanoid (Taito 1986)
• Lode Runner (Irem 1984)
• Mario Brothers (Nintendo 1983)
• Donkey Kong 3 (Nintendo 1983)
• Phoenix (Amstar 1980)
• Pleiads (Tehkan 1981)
• Traverse USA (Irem 1983)
• Pooyan (Konami/Stern 1982)
• Kung-Fu Master (Irem 1984)
• Super Bagman (Valadon Automation 1984)
• Donkey Kong Junior (Nintendo 1982)
• Bagman (Valadon Automation 1982)
• Omega Race (Midway 1981)
• Nibbler (Rock-Ola 1982)
• Vantris (Norbert Kehrer 1998)
• Space Invaders (Taito/Midway 1978)
• Pengo (Sega 1982)
• Amidar (Stern/Konami 1982)
• Ms. Pac-man (Midway 1980/1981)
• Scramble (Konami 1981)
• Galaxian (Namco 1979)
• Centipede (Atari 1980)
• Frogger (Sega 1981)
• Donkey Kong (Nintendo 1981)
• Pacman (Namco 1980)
• Asteroids (Atari 1979)
• Night Driver (Atari 1976)
• Astro Fighter (Data East 1980)
• Space Duel (Atari 1980)
• Black Widow (Atari 1982)
• Dominos (Atari 1978)
• Asteroids Deluxe (Atari 1980)
• Gravitar (Atari 1982)

http://web.utanet.at/nkehrer/