Handheld gaming systems have traditionally been crappy next to home consoles. GBA was a SNES compared to GameCube, GameGear was a Master System compared to a Mega Drive/Genesis, and PSP is a PS2 compared to PS3.

But every once in a while, someone manages to do the impossible and convert a game between the two tiers. Sounds dangerous in a 'crossing the streams' kind of way. Imagine every crappy port you ever knew, simultaneously exploding at the speed of light. That kind of thing.

We're not talking about handheld 'versions' of games like GTA Chinatown Wars on DS or MotorStorm: Arctic Edge on PSP. Those are new offerings, built with the handheld platform in mind. No, these are the real deal, converted so well we have to check the back of the console to make sure it doesn't have a tiny wizard stuck in the cartridge slot.

Above: Sometimes it pays to check - it was Gamedalf all along 

So here they are: the greatest handheld conversions of all time:

Street Fighter Alpha 3

Converted from: Arcade (1998)
Converted to: Game Boy Advance (2002)

2D fighting games may look simple to make. They're just hand-drawn pictures after all. And PSP has an arcade-perfect version of Street Fighter Alpha 3, so surely that's the point proven. But it wasn't the first handheld conversion. No - Game Boy Advance was doing it a mere four years after the arcade game's release, back in 2002. In style.

Above: Street Fighter Alpha 3 in tiny-vision. Aw, ain't they cute?

Unlike PSP, it's not an arcade-perfect conversion. That would have been an impossibility. But how close is 'damn close'? Well, there are some shortcuts like some omitted backgrounds and music. Then there's the way Ken's voice is put through a pitch-shifter to make Sakura's higher battlecries. It's a small price to pay for a roster of thirty-seven beautifully animated characters. For a 64meg game, that's just insane.

The 60fps movement, beautiful hand-drawn art and classic Street Fighter gameplay are a revelation on GBA. Especially if you stick the cart in a GBA Micro - you've got an entire arcade cabinet that fits in your shoe. It's cut down, yes, but never scuppered.

Above: GBA's conversion is so good, Ryu and Gouki are dancing with joy

Gunstar Heroes

Above: There it is. Sure, Red has a helipack now, but look at Seven Force!

Treasure overcome the limitations of low-tech hardware by running lots of tiny sprites in familiar formations, such as the running man form of the boss 'Seven Force' above. Moving the foot sprite beneath the knee sprite, for example, creates a convincing illusion of 3D animation. The CPU's happy because it's moving tiny things, the gamer's happy because he's seeing massive things. See?

Somehow, conversion team M2 managed to get the Game Gear to produce this advanced effect. Observe:

Above: Even Bravoo Man makes an appearance with only 2 fewer boxes 

Of course, the Game Gear can't do everything. Mega Drive Gunstar Heroes features full-screen rotation, which Game Gear can do... but only if you move your hands in a steering wheel kind of motion.

That's a bit low-rent, so some of the more technically complex scenes are adapted instead. But considering it's more faithful to the original than the GBA remake, including that revolutionary weapon system making it across intact, Gunstar Future Heroes on Game Gear is an outstanding achievement.