Play Retronoid
This game can be very tough at first. It's quite fast-paced for an arkanoid clone, and getting the powerup that increases the speed of the ball only makes it faster! That's what makes this cool: powerups. You can get a heated ball which goes right through the blocks, destroying them in one hit. The aforementioned speed incrase should be avoided, I think, while the slower ball is helpful to your survival. There are lots of powerups, and it's useful to memorize what's what for some should be avoided.
You can build your own levels, but it seems tedious. It's up to you, but the game has plenty of built-in levels for your enjoyment. The controls are simple - move the mouse left and right. I had a little trouble by moving the mouse out of bounds at first, but you get used to it. This is probably the greatest version of the classic arkanoid game I've ever played.