A Hudson rail bender, fitted with a hydraulic motor which takes a lot of the hard work out of bending steel rail. Ex-Perrygrove Railway, we acquired it to lay our new 15 inch gauge line in S10 (20lb/yd) rail.
With a fork lift in the yard here at work, we would never normally consider lifting such a thing by hand - however no such luxuries up at home where it was needed. So: four strong chaps can lift it off the floor and put it on a wagon chassis. Just. You do need a sit down afterwards though...
Complete with quick fit hose connectors and spool valve - you will need a power pack (we use a petrol driven one, we've got a couple of compressed air powered types we use at work, you can also get 12 volt electric ones inexpensively. Alternatively, plug it in to your tractor's hydraulics).