1. create cylinder, name it "Coin"
2. scale so it's like a coin
3. Choose Window>Animation Editors>Expression Editor

Now, in this window, we can do all kinds of things to "Coin." I had planned on making it spin faster and faster as time went on, but I can't seem to get it right.

I thought that you could write something like the following, but it won't accept it. (this is roughly what the values would be)

if (time = 1) Coin.rotateY = time * 10;
if (time = 2) Coin.rotateY = time * 100;

and so on. I can get it to spin continuously with this expression -
Coin.rotateY = time * 100;
I just need it to increase over time.