From the Daily Click (altered heavily):

Crossworld Island is a freeware online platform game. You can build your own world and have up to four players at the same time. You can also develop campaigns with the campaign editor or build your own chat room. The online rating system sorts out user levels which can't be solved. Coins can be collected to buy special items such as the elastic spring, which can then be used in any level. Click here to download the 70MB preview video.

Features:
- login system
- level editor for own levels and campaigns
- objects and tilesets which you get step by step
- an online shop where you can buy items with your collected coins
- a living room which is like your own chat room
- you can choose between different characters with different characteristics (e.g. the diver can dive, the peasant can plant plants and the mechanic can repair things)
- day/night system which is controlled by the server. During the day, the levels are different than at night. For example: Ghosts can only be seen at night.
- wind affects the game. In the level-editor you can adjust the wind
- slippery surfaces. ice blocks can be placed in the level-editor
- teamplay. without teamplay you can't solve some levels. everyone can choose what he wants to play before the level is loaded.
- collecting. if you finish a level successfully, all collected coins and items will be placed in your online account.