An alternative unit of Force
I humbly put forward the Yoda as a unit of Force.
Now before you all start groaning at the lame-ass pun, hear me out. The little green guy is capable of quite a large amount of thrust, as we saw in Empire Strikes Back when he lifts the X-Wing out of the swamp. Randall Munroe does a considerably better job of explaining the details: http://what-if.xkcd.com/3/
However, Mr Munroe's calculations only give us the potential wattage produced by application, not the force output.
So, based on the supplied mass of an X-Wing as 5,600kg (5.6 metric tons) and acceleration of 0.39m/s2:
5600 x 0.39 = 2184 N
Quite a lot lower than a charging elephant but 20 times stronger than the Norris. Hmmm. More thought required with regards to scaling here.