There was once a company called GetAFreelancer.com. Then they bought the web address Freelancer.com and changed their name. It is now one of the biggest online freelancing platforms in the world.
Attribution: Flicker - Widjaya Ivan
How much did this cost? The inside information that I have is that they were able to negotiate the price of the name down to only $350,000.
That seems like a lot of money to pay for a name. In fact if they had known what was to happen when they bought the name, they probably would have been prepared to pay the original asking price of 2 million dollars.
Once they had changed their name to Freelancer.com what happened was that if you typed nearly any search phrase related to freelancers into Google the results were dominated by freelancer.com. Allowing them to grow and dominate the market.
Online names are in many ways the real estate of the Internet. Just as having a shop on the main street is better than having one in a side street.
Of course names are not the only factor in having a successful website, however buying a better name than you currently have has been shown to make a difference. If you are balking at spending $20,000 on a name someone is squatting on, Freelancer's success might make you think again.