The red shells in Super Mario Kart are pretty useful, mostly due to their homing capabilities.

But they're not perfect.

Say you're in Battle Mode. You have a Red Shell and your opponent is stopped in the middle of a wide open area

You drive toward him and start to powerslide so that you just miss him

Then you fire the shell just before hitting him, so it sails right past

If done right, the shell will go around and around your opponent's kart, but since the turning radius of the shells isn't that great, will never hit him

Don't believe me? Check out this video

The shell will keep orbiting around your opponent until he moves or the shell hits something else on the course!

Of course, I was never able to find much of a use for this, other than it's something that looks kind of neat, but maybe you can.