Guest starring...who?

Remember that tingle when you saw the words "X-Men Vs Street Fighter" emblazoned on an stand-up cabinet in your local arcade? Maybe it was when you pitted the Daytona USA car against AM2's Palm Tree logo in Sega's bizarre fighting mash-up Fighters Megamix.

Whatever the moment, be it company crossovers, franchise mergers or simply a odd cameo, there was a time when mixing unlikely match-ups in videogames was a massive deal and more than a little bit special. Companies loaning out iconic characters to others was rarely heard of, and potential clashes were reserved to the letter pages of gaming magazines. Even intercompany smack-downs were few.

Now, we live in an era were Nintendo release Sega-developed F-Zero titles and Epic joke via Twitter about Marcus Fenix cameoing in Mortal Kombat. And while the magic is no longer as strong, there are still some crossover appearances that have taken us by surprise.

With Soul Calibur's producer whipping up discussion about future guest characters for the fighting series, it turned our mind to some of the weirder and whackier guest appearances over recent videogame history.

Link | Soul Calibur II | 2003

Much like finding the Holy Grail being used as a drink holder at your local dodgy drinking establishment, Link's appearance as Gamecube's platform exclusive character in Namco Bandai's Soul Calibur II shocked many, so resistant was Nintendo to farming out its iconic characters. Those hardcore fanboys crying out at his appearance were swiftly drowned out by roars of "cheap!" by other players, as Link had decided to bring long-range bombs and bows to a sword-fight. Aside from Super Smash Bros, this marks Link's only playable appearance outside the Zelda series to date.

Bizarreness rating: 7 (out of 10)

Mario, Luigi, Peach | SSX On Tour | 2005

Seeing Mario light up the various sporting competitions is now nothing new, running like an olympian through Nintendo-branded takes on football, baseball and the like. But thanks to a deal made with EA, we saw the Mario Bros replace cape and tanooki suit for a snowboard and a place in SSX's character roster. The three also shot some hoops in NBA Street 3 as well. It's a wonder the tubby hero hasn't lost that overhanging gut with all that exercise.

Bizarreness rating: 5

Sonic | Super Smash Bros Brawl | 2008

Read any gaming magazine through the 90s, or even be part of the culture nearly two decades ago and you'd be used to Mario and Sonic fan-baiting, the two icons spearheading the console wars of the era.

Hell didn't start freezing over here. That process started in November 2007 when Sega and Nintendo collaborated on Mario & Sonic at the Olympic Games, matching up the two icons for the first time in their history. Of course, the seeds were sown much earlier when Nintendo handed development duties of F-Zero GX/AX to Sega in 2001.

And even while Solid Snake's entrance into Nintendo's brawler might arguably have been better, this is what gamers over a certain age had waited nearly twenty years to see.

Bizarreness rating: 8
Bizarreness rating (if you're a 90s gamer at heart): 11

Ryo | Sonic & Sega All-Stars Racing | 2010

Of course, Sega weren't too bad at dropping their own surprises, while delighting and pissing fans off in equal measure. After a build-up of fan requests over the years asking for the return of Ryo and Shenmue, Sega delivered....sort of. Behind the wheel of a forklift truck (or a motorcycle when his special ability is unleashed) Ryo's appearance felt more of a cock-tease than anything.

Bizarreness rating: 7

Isaac Clarke | Skate 3 | 2010

You can't blame a spaceship engineer on the verge of a nervous breakdown for wanting to relax for a few hours in the sun. But while we'd already seen the likes of Wolverine grind in Tony Hawk, that the armour-clad workman-turned-Necropmorph killer tried to match the best that Port Carverton had to offer was one of this year's odder moments.

Bizarreness rating: 9

Guybrush Threepwood | The Force Unleashed II | 2010

...whereas this was just bizarre, and we still have no words for decision to plump Monkey Island's finest in this sci-fi adventure. Did it really happen?

Bizarreness rating: 10

Dante | Viewtiful Joe: A New Hope | 2004

A nice little piece of fan service this. Cameoing demon hunter Dante in the cartoon cinematic stylings of Viewtiful Joe might seem an oddball choice, but with DMC creator Hideki Kamiya and Clover Studios handling a PS2 port of the GC title, throwing in Dante as a bonus playable character was a cool addition to an already-cult classic. The two characters will be reunited in next month's Marvel Vs Capcom 3.

Bizarreness rating: 4 out of 10
Viewtiful Rating: 9 out of 10

Damn dirty apes | Metal Gear Solid 3: Snake Eater | 2004

Despite Sony's exclusivity over the Metal Gear Solid series at the time, few could have imagined the likelihood of this little mini-game gem sneak into MGS3. While Snake donned Altair's outfit in MGS4, the visual image of Snake trying to capture colourful cartoon monkeys from Sony's Ape Escape wins the prize for the oddest crossover for Kojima's prized agent.

Bizarreness rating: 8

PaRappa The Rappa | UmJammer Lammy | 1999

After the success of 96's short but quirky PaRappa the Rapper, gamers were eager to see the Masaya Matsuura's follow-up. Sadly, the combo of a new character (a guitarist, no less) and frantic-fret action didn't gel as smoothly with the action-rhythm rapping of the original.

However, while we should have expected a cameo by everyone's favourite doggy rapper outside Snoop Dogg, the secret unlock did a lot more, opening up rap versions of the song list as PaRappa brought his own playstyle to Lammy's stages, effectively giving you two games in one. It was a massive, but very welcome, surprise.

Bizarreness rating: 7