im sure you all know this has a huge effect in the game, allowing you to climb anything, jump from great heights etc. But i thought id share with you all the actual origins of altairs skills.
A while back, the BBC showed a show about a new urban sport known as parkour in which some french dudes did some crazy stuff in famous london sites. (the link below has some pics)
I especially like the close link between assassins creed's ideas of illusion and parkours feeling of "Human art form".
This was one of the reasons that AC excited me so much
Anyway, check out the sites, go find some rooftops and pretend to be altair.(but please, leave out the murder )