Just an idea on a fun badge... Say a user gain lots of reputation in short period of time (to be determine (X amount of points and Y amount of time).... he is a climber or rising star, etc. etc. Pick your wording.
I like this idea. Call it "Ascender," "Rising Star" (as suggested), or something else entirely. I'd put two conditions on it, though:
- User has 5 consecutive days (I say 5 for those that take weekends off) of 190 rep gain (kudos to Kyle for catching the downvote issue)
- User has < 5000 rep (otherwise you'll hit the issue where folks with high reps and lots of posts get this badge every day).
Rather than a points based badge why not have a badge for the biggest mover of the day in terms of moving up the users list.
Or how bout having the badge based on an equation which takes into account the amount of upvotes compared to how many times the question has been viewed (so that its not just the c# answers that get the badges). Lets give a little consideration to the less popular questions.