I used the same stuff - different brand name- to take molds of my forks and dropouts to more precisely lay out my torque arms and plates. It REALLY helped get things right the first time. I only messed up on the parts I DIDN'T use it on.
Several other things I plan to use it for, but haven't gotten around to yet. The only other thing I have actually gotten around to doing so far is making ergonomic handles for some of my hand files.
For instance, You could use it to make an instrument holder to put on your handlebars, if you live in a place where it doesn't get hot and super sunny.
If I had a ton of it, I'd use it for lots of stuff around the house and shop.