@mnementh - you mean like a portable PowerJoy, the 82-in-1 cart?

1. Metroid 2. Not as good as some of the other Metroid games, but still a fantastic game in my opinion.
2. Super Mario Land 2. Best platformer on the game boy.
3. Radar Mission. This is out of left-field. I'm not sure anyone else remembers this, it was two games in one. One was based on the battleships board game and the other was a shooting game that put you in control of a submarine. Hardly any one has ever heard of it but it was an excellent game.
4. Super RC Pro AM. Similar to the Nes versions and a very enjoyable racing game.
5. Kirby's pinball. I'm yet to play a better pinball game, even after all these years.

it's this one:
http://www.gamersgraveyard.com/repository/gameboy/pirate/pira...

it's very cool.. my parents bought it to me as a kid, it's from the far east. It's illegal though, it's like pirating of today all the rom's (so it's not something I endorse regarding my Wii...).. it's a double sized gameboy cartidge with a reset button. It has 82 games including Tetris (which I didn't need but could use for multiplayer), and Super Mario Land.. also Tennis, Burgertime, quite a lot of excellent games. Here's the list, although not 100% accurate:
http://www.gamersgraveyard.com/repository/gameboy/pirate/82-i...

Super Mario Land 2? really? I thought the level design was so bland and poorly thought out for the most part. The enemies were so random, and there was practically zero challenge. At least the World Map was great, and I liked the Carrot/Rabbit ears Power up. Yet I found the first Super Mario Land overall to be the better, more quirky, challenging and fun experience.

Oh and add the first TMNT GB to the list!
Anyways, Zelda LA was amazing, and Wario Land was fanastic. Kid Icarus MOM was a nice little suprise, not quite sure if I liked it more than the original...I wasn't big on the level design since you could never fall to your death. But i loved how the mallet was better utilized and the dungeons were less frusturating and more fun this time around, but the music while good doesn't hold a candle to the original The Original had mode charm and it's easiy one of my favorite games of all time, I have such fond memories playing it when i was 6 years old I also reallly need to play Castlevania II: Belmonts Revenge(although rare and expensive) and Kid Dracula

Hell I'd easily give up my copy of Jack Bros(complete) for the Virtual Boy fir Castlevania II: Belmont's Revenge.

1. Link's Awakening
2. Pokémon Red & Blue
3. Wario Land: Super Mario Land 3
4. Mega Man: Dr. Wily's Revenge

I was never able to play it, but I heard good things about MegaMan V. But in terms of games I own, I would supposeLink's Awakening.

Donkey Kong '94- If I had to pick one game to be stuck with forever on a desert island it would be this one. It has everything you want in a game, it's a puzzler, a platformer, just a great way to kill time. It's the perfect evolution in the Donkey Kong series taking the original and adding in Mario's growth from the SMB series. What I would give for a new WiiWare sersion of this.

If anyone gets the opportunity to play Mega Man 5, it would go up on many of your lists. Metroid II was really good too. The TMNT games were all good, Darkwing Duck is fun but incredibly difficult, and I really like Street Fighter II. I don't know how rare this game is, but I picked up a JP version of Fatal Fury that's pretty good, even though everything is chibi.

Nobody has mentioned this one yet, but my favorite is Final Fantasy Legend II. Next favorite is Final Fantasy Adventure. They're the perfect Gameboy games.

sounds like choplifter 2. i owned this one as well and my cousin and me played it till our fingers bled ...

@topic: at that time i was a young kid and selected games more for the cover than for the possible quality so my list might well be awkward to some back then i particularly enjoyed (in no particular order):

mercenary force
turtles 2
super mario land
tetris
probotector/contra
gradius
burai fighter
parodius
motocross maniacs
chase hq

and probably a lot of other games i don't remember right now

I'd have to say the best is easily the Pokemon games, I'm sure people have spent dozens of hours on their Game Boy's because of that game. Besides that, I'd say Zelda: link's awakening, Donkey Kong and Mario Land.

1. Donkey Kong
2. Mystic Quest
3. Tetris

Seiken Densetsu! Just as the remake Shin Seiken Densetsu was the best GBA game. So I see people on this thread referring to it as Mystic Quest; is that what it was called in Europe? I hate calling it Final Fantasy Adventure, just like I hate calling the Saga games FFLegends.

There are so many...

Yes, I'm from Europe and my Seiken Densetsu ("SECRET OF MANA 1") game on the Game Boy is called MYSTIC QUEST. I love this game.

Pokemon Red

pokemon blue

Links Awakening duh

The Legend of Zelda: Link's Awakening

Tetris is still my fav Gameboy game of all time.