Even the best Drupal site need traffic. It would be terrible if you put a lot of effort in building a good site and some brandname and someone else would benefit from that and "steals" some of your traffic.
One of my sites is www.StockTrendInvesting.com . As you can see it uses the .com extension. I also bought now the .org and .net UR's with the same name. The main reason for that is that I did not want anybody else to start a site with a very comparable name.
Till today, I did not really do anything with those .org and .net sites. I just bought the URL so that nobody else could use them.
Today, I forwarded those .org and .net URLs to the .com URL, using the service from the company where I buy and keep my URLs (www.godaddy.com). I do not expect any real traffic from this, but it cannot hurt either.
What else could I have done with these URLs? Please share your comments.