I present for your consideration Jerome Harrison.
In three games this year, he has 16 carries for 109 yards, yielding a 6.8 average. 11 of his runs have been successful*, giving him a 69% success rate. He also has one reception for 15 yards. 11 of his runs have come on first down, and he hasn't had any third-and-short runs, but thats more a result of his success (he keeps running for 10-15 yards on first down).
Beyond his successful stats, the kid's running has just been exciting to watch. His cutting and spinning have helped account for at least a chunk of those 109 yards.
Now, I'm not saying he's ready to be the feature back, but based on his production, I'd like to see him get more touches.
* Gaining 40% of the yards needed for a first, or 100% on third down