Ah, Lego, don't tell me you don't have a deep down love for the little plastic bricks which made everyone's childhood just generally... Better. 

If you dig deep enough, on the internet, you can find Lego Digital Designer and it's little brother LeoCad. LeoCad is similar to LDD, but LDD is better for beginners. LeoCad can open LDD files, and convert them into various 3d models. 

I've played a lot of the TT Lego Games, and am yet to see any fan games of the big franchise. That's your task! Create a Lego Fan game! You have until Midnight on the 5th of October.  Go Go Go!