That's cool. My multitool doesn't have one and my home tool is much, much larger[1] (160 x 100 x 22mm, 242g). I guess if I were buying a new multitool today, I'd try to get one with a chain tool included, but I also don't feel a pressing need to carry one. I've never broken a chain while riding, nor do I know anyone who has broken a chain, and I ride with a lot of cyclists putting out 600-1000W in sprints.

[1]: http://www.birzman.com/products_2.php?uID=2&cID=31&Key=54