All the other glitches I encountered were pretty entertaining. Another one was the duplicating glitch in Mario Kart Wii. This is really helpful too. Also, anyone has heard of Daisy's 3rd eye in Super Smash Bros Melee?
Taking advantage of Mario Kart Double Dash's crappy physics is awesome too. An example is making the kart upside-down and remaining like that in Bowser Castle.
How about the Mario & Luigi Superstar Saga glitch? The one with Mario levitating high up in the sky after he got hammered by Luigi (before Hammer abilities). It occurs when Mario goes into the drinking fountain.