I started tinkering with games very, very early on. One of the most ambitious homebrews that I ever did was basically making Battlesuit, the man-to-man tactical game set in the OGRE universe into an rpg.
I no longer have the notes for that game as the binder was in a trunk that my dad gave away after I turned 18 (it was a misunderstanding on his part). I remember meticulously handwriting out pages and pages of notes on skills, classes, attributes, battlesuit options, combat, you name it. I kept the original "dot map" (Battlesuit's map used dots instead of hexes or a grid) for movement. I also kept the combat results chart and 2d6 rolls, and had attributes as modifiers to the results. I remember MERP and possibly Palladium as being inspirations for the system that I finally came up with, but a lot of it was pulled from an old Atari game that had battlesuits in it as well.
We actually played several sessions of the Battlesuit rpg rules, but it became evident pretty quick that it might be easier to just use another game system (like Heroes Unlimited or later on Mekton). I'd give anything to be able to see those old hand written notes though. What truly horrible ideas did it have in it? What strokes of game-design genius? I just don't remember any more.