Here's a great clip…Spike Jones and his City Slickers playing "Yankee Doodle Dandy," complete with a Jimmy Cagney impersonation by Billy Barty. The visual gag of Spike sitting on the piano with his feet playing the keys was devised for him by the great animation director, Tex Avery. Matter of fact, I have Tex's original sketches for this gag here someplace and if I can find them, I'll post 'em one of these days. In the meantime, here's my favorite bandleader and my old pal Billy making George M. Cohan spin in his crypt…