Honestly, I'm having tons of fun with really old viewfinder or DSLR lenses. If I had a bit more motivation I'd figure out the electronic lens protocol of my Sony camera, and program a microcontroller to drive an extension tubes and make autofocus lenses out of them.

So yeah, if you're willing to do without AF, and especially if you're doing video, it's difficult to beat a fairly sharp 50 1.4 for 50$