Ditto Glitch

I found this at Bulbapedia.  See, you can have Ditto know other moves with this.  However, it only works with HeartGold and SoulSilver.  What you do is if you have a Pokemon with Rage, put in the front of your party with Ditto.  If you don't, get one.  Then, go into a Double Battle.  Have Ditto transform into your other Pokemon.  Use Rage as Ditto until the PP runs out.  Don't win with Rage, use a different move to win or you will have a normal Ditto.  Then, win.  Check your Ditto, and it will know all of the moves it knew as whatever Pokemon it was in the battle.  You can do this with any Pokemon.  Just put your Pokemon that wants new moves with Ditto, and do a Double Battle.  Then, have your Pokemon use Metronome, (although Transform Might not happen,) or any of these moves on Ditto on the second turn:Mimic, Assist, and Copycat.  Then, switch Ditto out with the Pokemon that knows Rage.

P.S., I haven't tried this, I only saw a video.  Tell me if it works, and I'll tell you as well.