First there was Subservient Chicken, Burger King’s advertising gimmick where you could type in commands and, if they were within the applet’s repertoire, watch a guy dressed up as a chicken act them out.
Then there was Subservient Programmer, which is the best of all the subservient applets I’ve seen. The animation loops are most carefully timed to create the illusion of continuity. There is also a wide range of commands available.
Now there’s Simon Sez Santa. It is not as well-looped as Subservient Programmer, but the sound effects are funny. If you choose the naughty version, make him drink a beer. :p There’s also a kid-appropriate version so you can show him to little ones.