Well I'll be coming back I think! I was looking at the RMU material and it's been nice and interesting so far, but then I'll come back and look at HARP and I remember why I like it so much.
I joined up a D&D4e group, but the DM got busy with work and school, so I think I just inherited the iron gauntlet of power. So They'll be going from 4e to HARP, which will be interesting.
When I was running HARP a few years ago in college I ended up utilizing a lot of house rules... which mostly seem to have been integrated into the new HARP Fantasy, which means I'll probably be running it without all my house rules. Except how I plan to handle inventory. I want to try out this idea of using index cards as "bags" and such, and items have sizes which take up lines on the card. This lets players Tetris items onto the index cards, and then instead of worrying about the weight, you just see how many index cards the character is holding. When they need to move around in combat, they can "drop a pack" and flip the card over, and if they want to access an item they have to return to the pack. Also makes it easy for the GM to track the player's inventory! But I'll post that when I refine it a bit.