For those who don't know, SAGE stands for Sonic Amateur Games Expo. SAGE is an event that occurs every year, for people to showcase their Sonic fan games/fan engines and much more for others to see and vote on wich one is the best.
For more information go to SAGE's official website at:
http://sagexpo.org
Have fun!
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In case I posted this on the wrong forums, mods please do feel free to move this if you so wish.