Built some wheels for a racer buddy of mine. He wanted light and he got it. 575 grams for the front and 1010 grams for the rear. The rear is running a power tap hub which is why it is fairly heavy compared to the front.
The rims are from one of the "China carbon" companies out there and the front hub is from bikehubstore.com It certainly does not look like the most durable hub out there with some rather small bearings but if you are building a race wheel, replacing bearings once or twice a year is not that big of a deal. Other than the tiny bearings it looks like it should hold up well.
Obsession, or passion? Who am I to judge? Either way I simply love building wheels for those who appreciate quality!