Lotto Zheros and KSLs. They are amazingly light, and compared to the vapors are much more comfortable.. IMO..
Many have been named but for what's it worth, I'll add on to the current ones. If I'm not wrong, Nike Mercurial Vapor is still the lightest boots around with a weight of 7.1 Oz. Nike Mercurial Talaria (7.4 Oz) Lotto Zhero (8 Oz) Umbro Elite X Lite (8.8 Oz)
Shoes i have that are comparably light as vaps zhero nove got 2 Azt iiis and 2 vap iis and frankly, the vap iis are the friggin lightest boots ard.. zheros are light and comfy
asics tigreors are almost as light as the vapors. but are wayy more comfortable and durable. i just got mine a few days ago and so far i have liked them a lot. and u can get them at the site tahts on another thread for like 70 US dollars with shipping.