From the private archives and "HTH" classic:
Nobody (outside of a small handful of people) will ever get RICH (I mean private jet, own an island, hang out with the president rich) by just doing domains and churning out crappy pages.
Real money is made by building a business, and a real business is not built around the domain, the domain is a marketing tool, a path to the product, perhaps even a portal or a wealth of information that people return to, perhaps the domain is even the brand itself.
I see so many people say "i own this domain, should i build a business around it?"... this is just light hearted wishful thinking, if you're basing the entire business model around the fact that you own a domain in the market, you are probably not going to succeed.
My personal way of using domains has been to come up with an idea, develop the plan, evaluate the viability of the plan, and if it is worth while then buy domains relating to the product, and develop the product around the best domain in the portfolio.
I'm not trying to discourage anybody, but there are only a few people with domains like property.com... the rest of us can't just sit around waiting for somebody to scoop up our portfolio for a billion.
The bigger problem with most domainers is that they went after domains with *ZERO* regard for the theme of each domain. In other word there is *ZERO* intrinsic synergy across their portfolio. In my case I purely went after domains within a common theme and so there is no "site", there is a network of related sites.
But when all your domains are totally unrelated there is no synergy and the work to develop increases by orders of magnitude.