...an idea, or the start of the fic done, you could post it and see if anyone picks up on it. I've done a groupfic before, where no one had time to write the ending. I came along, saw it was just sitting there and asked about an ending. Two of the co-authors suggested I make one, and I did.
So, like I said, go ahead and post what you have and someone might find it fun to add something.
Good luck.
