Git rebase UI

I am in middle of designing a UI for interactive git rebase,
But i am getting into quite a few usability decisions to be made.

So i was wondering has anybody implemented or attempted to implement
such a thing before, from which i can _not_take_ mistakes/reinvent the
wheel (or atleast redesign it).

Googling doesn't give me any, so i thought i will ask if somebody has
it in his private closet.

Thanks,
BAIN