Just how much do you know about local artist Daniel Johnston? Enough to play Captain America or Joe the Boxer on stage? Convincingly? If you happen to have two Johnston pieces in your repertoire, check out this little gem we spotted in the current issue of the Austin Chronicle: "After two wildly successful runs at Houston's Axiom last year, Jason Nodler's original rock opera Speeding Motorcycle, based on the life and music of Daniel Johnston,......