I have devised a new system for the HERO game that I am running on weekends. The setting is post-apocalyptic, but I believe it could be applied to any game with relative ease.

But first, some backstory. There are a number of elements that I like from systems that aren't HERO, that HERO doesn't model particularly well (or, more likely, I just haven't really put the effort into modeling them well).

I like Willpower from White Wolf, insofar as I like players to have limited charges to exceed their limitations. This is, mechanically, not too different from D&D's optional Hero Point (or possibly Action Point? I forget the nomenclature of the original implementation) system, which gives you extra bonuses to apply to your rolls (except for damage). Well, except for the fact that Willpower in WW games was significantly more character-defining -- that was your character's WILL, not just a pool of points to spend to accomplish ... eh ... stuff.

I like RP bonuses, which WW models as bonus experience points for 'the best roleplayer' of the session. I also like EXP bonuses for players doing well, or being clever. But these tend to run the risk of rewarding some players more than others, throwing all of your player characters out of balance with one- another.

I like Drama bonuses, which Exalted (another WW system, of course), uses in the form of Stunt Dice, which is bonuses to your rolls for being cool (which is a little bit like hero/action points AND RP bonuses, if you do it well).

But I'm mostly going to focus on the 'rewarding your characters for doing well' part here, with the system I came up with. Specifically, with the interest of balance, the system goes something like this:

Experience for the party is 1 point per player per session. Uncovering critical plot points, snappy and clever dialog, good RP, heroic rolls that defeat the odds.... These things are worth additional points.

But the players are not actually directly rewarded for their individual efforts (beyond what their RPing in game accomplishes, etc.). So, all of the total points accumulated by the party are put into a pool, divided by the number of players in the group, and the remainder is just carried over into the next week. This means that your star RPer is boosting the entire group (albiet, more slowly), instead of slowly RPing his way into a massively more powerful character than everyone else, so they have to follow in that player's shadow. It also means that the guy who can't RP as well because he's new, tired, has had a bad week, etc., can still contribute to the pool by doing well, thinking to look places someone else might not have, and so on. The guy who gets the most kills might also boost the pool ... but the entire party benefits, instead of just him.

It does diminish the factor of individual rewards for individual contributions, but again, some of that has to be handled in-game, not in the post-game reward session for EXP. Weighed against the potential favoritism (if you let players know when they have earned points for just themselves), I find this system quite satisfactory. Admittedly, because it's largely anonymous (that is, invisible to the players), your players won't also subconsciously (or consciously) play to the GM and game extra points.

It also helps overcome favoritism (however accidental) in favor of party balance, if some players are just more 'earney' than others.

Long system short: For game balance, all EXP is pooled and split, and I still get to reward players for being awesome or just doing cool stuff.

Also, evidently I am an honorary Uncle. Welcome to the world, baby nephew Orion.