The Eyes Have It (1945) - Donald Duck laughs nastily and glances over at Pluto, as he's about to hypnotize him using a pair of hypnosis goggles, to morph him into various animal forms.
First saw the cartoon via the Donald's Birthday Bash VHS - one of the best I have ever seen. The plot, the animation, the climax, the music, all wonderful. Other classic featured in the cassette are Contrary Condor (1944), Wet Paint (1946) and Clown of the Jungle (1947).