I've worked on two.
I did one update, and started work on a full game of my own.
The update I was doing was to the Kimagure Orange Road RPG, which can be found here:
http://www.geocities.com/Area51/Corridor/4286/korrpg.txt
The idea was to convert it from an anime-themed roleplaying game to more of a "college weirdness" RPG.
Basically, I cleaned up some of the rules, corrected some grammar, and expanded the psionics list a bit, including rules for "latent psionics" for average joes as opposed to full-fledged espers. For example, instead of teleportation, you had "convenient entrance" meaning that your character could walk into a scene from a door or window that nobody was on the other side of, even if there was no way for you to get back there in the first place, e.g. a closet or a bathroom, as long as nobody could see you arrive there. There were lots of other "incidental" powers like that, and it looked like a lot of fun.
Then I accidentally rm -rf / that computer. Ouch. Never bothered to go back and do the changes.
The second one was an anime-based RPG, that was based on a 2d6 system combined with cards ala TORG. There was a three-way "trump" system - Humorous actions trumped Dramatic actions, Dramatic actions trumped Realistic actions, and Realistic actions trumped Humorous actions. So if you made a horrible joke (an actual attack), and somebody shot you (a realistic action) your joke would be negated, but you could make a pathos-filled speech, while dragging yourself to your feet clutching the bleeding wound and threatening the shooter's very mortal soul (a dramatic action), which would negate their attack. Somebody pointing out a humorous oversight of your dramatic speech would negate its effect, etc. Negation could actually be done from any of the three types, it was just easier (+5 bonus IIRC) from the type of action that trumped the action taken.
There was also a "pawaa appu" effect, through the cards, that helped to simulate the anime-style of being beaten into a bloody pulp by a superior opponent, then dragging yourself off the ground, wiping the blood off your mouth, and proceeding to open up a can of whoop-ass on the perp who did it to you.
I ran into trouble getting the cards to work right, gave up on it, and never came back.