Scratch

Minecraft

Minecraft is a single and multi player game based on placing and destroying blocks of different materials. It was based on another game, infiniminer, but with various changes and improvements the game has really grown and continues to expand on the ideas of infiniminer.
It began its life on May 10, 2009, at the hands of Markus Persson (Also known as Notch, bald, and swedish) It's currently free to play Minecraft Classic but to play "/game/" you have to pay:

+ 9.95 Euros
+ £8.53 (as of 31/06/10)
+ ~$12-13

via PayPal. The price will double (it is currently half price) when the game reaches beta stage.

Classic:

Singleplayer:You click single player on the front page and the level is generated, you have deep seas, sandy beaches and rolling hills. Huge cave complexes beneath your feet, ready for exploration. It auto generates forests and other features. As you stroll through the many valleys, you wonder, where are the houses? You right click and to place blocks, and press B to change which block you are using! You can set all the blocks from 1-9, then use the keys to select each one. You build yourself houses and fortresses using glass, wood, stone, cloth, anything and everything you can think of. Fun?
Multiplayer:This is where the fun with other players kicks in, you join up on the server. Bang in front of you are people all around, grand structures being built. Some of it is truly awe inspiring, you get lost in the maze of buildings, murals and towers. Want to build a Megastructure? Now you can do it with friends, meaning you can make it twice as epic in the same amount of time it would of taken you alone.
Alpha (PAID)
If you have bought the game, you'll gain access to /game/ (And the downloadable client). The goal: survival! You are stranded in the middle of nowhere and you need to survive (obviously). Cut trees to get wood, which is used for a variety of tools. In the day, sheep and pigs will spawn, which can also be used for food and cloth! However, when night falls, evil monsters appear which are ready to make your experience of Minecraft a lot scarier! Build huge castles and underground system to protect yourself from these monsters and dominate the forsaken land of creepers, spiders, zombies and skeletons! /game/ generates infinte maps, so you can explore forever!