I have found several domains that have a clean history and a few backlinks each. Nothing spectacular really, most of the links are web 2.0. They are not exactly in my niche, but related, like golf ball - golf course. Now I'm wondering, do you have a rule of thumb or anything by which you decide if a scraped domain is actually worth registering? I'm not asking how to find out if they are clean or not, what I mean is, how do you judge at what point the link juice from a scraped domain is worth more than the costs of registering it and the time to set it up. I don't want to sound cheap, but if I register say 100 domains, that would add-up to a nice little sum. Obviously I could boost the scraped domains with 2nd and 3rd tier links, but that would delute the natural looking link structure that I'm aiming for in the first place.