On this topic, I am currently taking a Ruby programming class and my plan for the final project is to build a CC-like game. I don't want to de-rail the discussion here so I will most certainly add its own thread when I start on it, but my plan was to have all the basic game elements (with some obvious differences), but the major change would be the adding of a checkpoint system and game-saving that works, and maybe health/shields/killing monsters of some sort to help alleviate this problem entirely with stupid monster deaths or pushing of blocks in a corner or irretrievable areas. I just thought it was worth a mention for now, so don't let it distract you all too much. 
Yes, yes, I know about copyright. I won't use the same graphics or anything like that.
Yes, yes, I know about copyright. I won't use the same graphics or anything like that.