I really like the Michelin Pro2 Race tires. (oops, but I see they're 220g - but that extra 40 g = 1.4 ounces, so it's really not much). My DH has some tires that may be lighter, but I don't recall the name...I'll edit again when i get the name)
They come in a light grey/nearly silver (but perhaps not at this link).
DH has Vittoria Open Corsa Evo's. Also not under 200g, actually, the're listad as 230g, but very nice.