
The game is freeware but not open-source;
downloads available for Windows and Mac OS X ... but (sadly) not for linux (yet???).
Quoting Marble-Arena.com:
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Zap your way to the top in this exciting new game. Control your marble around easy to intricate levels, up and down slippery slopes, mastering physics contraptions such as jumppads, air vents and vortexes.