I've noticed many companies registering typos of their names but not redirecting them to their sites.
When someone registers a typo they sue him because they say he profits from their name ( traffic )..although it's obvious that when someone makes a typo and it redirects him to a completely different page, he will look again for the site he was originally interested in.
But check out this:
plaboy.com - belongs to Playboy, but isnt redirected to their site
aolmessanger.com - belongs to AOL, but isn't used anyway
googlesearch.com - belongs to Google, but doesnt redirect to their site
All these names get massive type in traffic every day and the companies that own them still dont feel the need to forward these names to their sites. It really amazes me
