A few suggestions for your new junque
The carriage bolts make good mushroom stakes.
The bridge plates make excellent hardy tool plates (bolt to a stump).
If you cut off the part that the train rode on you can make a good very small bickern out of those short sections of rail (use the web as the shank, draw one side of the flange to a point).
I'm sure you'll come up with some creative uses of your own, too -- please post 'em!