I've recently stumbled upon the ability to install other keyboards through Windows, and I've installed a few languages and the US-Dvorak keyboard as well. I've been trying to learn it blindly for a while now by retyping text files to build muscle memory, but it's difficult to remember where all the keys are.

I was thinking that it might be good to learn it by repetition similarly to how I learned the QWERTY layout, but I'm having some difficulty finding anything. What (preferably free) software is available to help me learn to type with Dvorak?