You need to have the right structure and protections (to cover your ass).
Think of it like a pyramid....
white hat site
Foundation sites - rarely interlinked but all linking up to your white hat sites.
Lot's of Black Hat sites (yacg, splogs, scraped content - ie shit you can put up fast -- all these link to your foundation sites.
You would be using xrumer on your black hat sites.
Click my sig if you want to learn more - click the link at the top that says 30 days to a kick ass foundation.