InstaMorph is just another name for polycaprolactone. There are a lot of different names for it out there (I got it as Missing Link Plastic), including Shapelock, PolyMoprh, Plastimake, etc. It's pretty neat stuff, and I heartily recommend getting some to play with. I've used it to replace poorly adhering grips on one of my sets of flush cutters and it works great.
I also made a glow in the dark jellyfish from it, but that was just fooling around. It's working temperature is way too low for scales, and while you can work it at 'solid' temperatures, it doesn't sand well.