So at the weekend I picked up Far Cry: Instincts. It’s a very good game – pushes the Xbox graphically in ways you couldn’t dream (trumping even Riddick) and has a great fun set of multiplayer modes.

What’s really interesting, though, is that it has an excellent mapmaker. Far from letting you just move around tiles, it lets you mould terrain, build structures, and plan complex maps – and then play them online with your friends. It’s been really well designed – the controls are superbly mapped to the Xbox pad. It still takes a while to make a map, but it’s not tricky to make some quite complex ones.

Anyhow. When you’ve made a map, you “publish” it – this doesn’t upload it anywhere, it just seems to verify it with your online name (Gamertag, in Xbox parlance). And then you can host games with your friends, with your map. They will, of course, have to download it from you, but that takes a few minutes, and then everyone can play.

Here’s where it gets clever. When they come to host a game, they’ll find your map – which they just downloaded – is on their list of maps. So they can host a game with the map you created. And if it’s a good map, they may well do.

And so then everyone they play with gets to use your map. And so, if you’ve created something really good, it’s going to spread virally very quickly; players will say “this map is good, man, you should play it”. At its logical conclusion, as many people will have your map as the ones the game comes with, and then you’ve entered canon. Wheras PC games (which are usually very moddable) have a distribution network of the Internet, Xbox games don’t have the same freedom for downloading new content. So Ubisoft should be applauded for letting the players become one big viral network, in which they ‘catch’ maps off one another.

The game’s online implementation has the customary Ubisoft online flaws, but in terms of how easy it is to make brand new content – and, more to the point, how easy it is for that content to propagate based purely on merit – it’s really something special. I can’t wait to see what happens when the map-makers get really good…