Stephen Jackson has been a star for the Rams over the past few years, having seven straight seasons with at least 1,000 yards. This season he has run for 403 yards over eight games, as his attempts are down. At the age of 29 he can still add something to the Jets offense. Paired with Shonn Greene, Jackson could become a lethal weapon for the Jets offense. Though it may be a little costly, I think Jackson would be a great addition to this offense.
Deangelo Williams of the Panthers is also 29, and has a little less mileage on him. This season he has rushed for 210 yards, averaging 3.4 yards a carry. Williams has not lived up to the huge contract the Panthers gave him, but still is a great weapon. He is quick and could really be a good receiving threat for the Jets on third downs.
I think Jackson would be a better fit for the Jets. Though you may have to give up some picks, he still has some left in the tank and could be a star for New York. I doubt the Jets will make a big move like this, but if they do you may see Jackson.