Breakout

Use a paddle to reflect the ball and knock out bricks.
http://www.geocities.com/~lschiano/Breakout.html

Batty II

Online version of the classic Breakout/Arkanoid game in Flash. Includes multiple levels and high score list.
http://polar-lights.com/free2000/batty_e.php3

Plopnoid

Online Java version of the classic Breakout/Arkanoid arcade game. Features 50 levels, sound effects, and bonuses.
http://www.mandrixx.net/plopnoid.html

Complications 2064

Fight mutated viruses that have invaded the earth in this online java-based Arkanoid-clone game. Includes statistics and highscore list. Requires account sign up to play.
http://beast.isk.kth.se/complications/complications.jsp

Panic Ball

Arkanoid remake featuring full screen game play, power-ups, high score list, and player poll.
http://www.panicball.com/

Smasher

Flash version offering 19 levels.
http://smasher.the-game.us/