Go to a place where there's a hole that you push boulders down(i.e. Victory Road). Ride your bike down it and, when you
hit the floor, the bike music will still be playing even though you are not on it.
If you get a Pokémon to evolve
after the final battle with your rival, the music will be muted until Professor Oak comes up to you.
First of all
you have to get Jynx and Scyther, or at least have their data in the Pokédex. Then go to the Pokédex, scroll down to Jynx,
select CRY, and while Jynx's cry is playing, QUICKLY go up to Scyther and select CRY. If done right the game will make a weird
sound. Note: you can do it with Mr. Mime if you don't have Scyther.
When you're in a trainer battle, and your Pokémon
is badly hurt and making that beeping noise, when the next Pokémon comes out, its cry will be messed up. Sometimes it makes
another Pokémon's cry, e.g. if it's a Kadabra it will make a Gastly cry.
OK, here's a strange glitch for Pokémon Red/Blue
for GB. It makes strange and even scary music by slowing down and mixing together music from pokémon Red/Blue. For this to
work you have to have beaten the elite four. First do the duplicate items trick with Missingno. with any item. Then go to
a pokémon center (preferably the elite four pokémon center)go to the computer and select Hall of Fame. Now scroll through
the pokémon (take time to look at them they're should be strange pokémon some that don't exist). If it shows the regular pokémon
you used to beat the elite four then save you're game turn it off turn it on again turn it off again and turn it back on.
Then look through the hall of fame somewhere in the hall of fame there will be a pokémon that says type Flying/Water and after
it says it's cry the music will change and doesn't change back until you leave the pokémon center and walk back in.
not sure if it works for blue or red, but on yellow go to Victory Road from Indigo Plateau. Get on your bike, and it should
still be playing the regular cave music!