How do people make thousands on domain names? (e.g. http://wealth.to - selling for over 50,000 dollars.. how?)

Answer 1

They register a lot of easy to remember domain names and then wait for a marketing person who wants one really, really, badly. Although, on the ones that nobody wants, they make zilch.

Answer 2

Those good domain names are taken. Those are domains that people will type in their browser in large numbers, and draw traffic to their website or parked domain.