1st Gen Glitches
 

Post any glitches that you have done in the first gen :)

Me:
Missingno. (Yellow)
44hy (Yellow)
Q (Yellow)
Aquachu (Yellow)
Mew Glitch (Red, Blue, Green, Yellow)
M (Blue)
Z4 (Red, Green)

I attempted the glitch in Green that was supposed to let me reach the Hall of Fame in minutes, but I was trying to go off the top of my head, so...

Let's say I failed miserably.

Glitch City. No way you can forget that one. :p

I actually brought my Fishing rod there once and tried fishing in the water.
Found the regular Pokémon from Route 20, but no Pikablu nor Togepi. D:

Oh so many. If they ever port R/B/Y to the 3DS I really hope they keep these glitches in, since they're one of the main reasons I've had so much fun with the games.

Glitch City
Missingno.
Fought Blaine along Cinnabar's shore, that's one heck of a battle.
Same with fighting Blue
Mew Glitch
Extended Mew Glitch/Ditto glitch to get ZZAZZ, which ended up corrupting my Blue save with a completed Pokédex ):
Traded various glitch Pokémon over to Yellow to see what would happen. Many interesting results, and many crashes. :3

There was this one time where I found a level 160-something Ninetales on the coast of Cinnabar when I was trying to pull off the Missingno. glitch. There was another time where I added a cheat which allowed me to walk through walls, so I went around Kanto and headed down to where Oak is supposed to stop you. Seeing as I was going towards Pallet, when the walking scene started, I went in the opposite direction of Oak. I think I ended up in Pewter before hitting the crash-zone.

Lol, I remember when I first got a Gameshark.
There was the Float-in-air cheat pre-loaded on it, so I went straight to the grass around Pallet Town.
Little did I know that grass was only there for decoration purposes and crashed my game as soon as I entered.