One important point I want to add on trademarks... Not only do you trademark in a specific category of goods/services, you also trademark in a specific location. So a trademark in the US protects your rights in the US. Someone in another country could obtain the same trademark for the same type of product in their own country.
All of which has very little to do with domains. Having a trademark is simply one way of demonstrating that you have a legitimate interest in a name which is one part of the UDRP process.
The most important part of the UDRP process in my opinion is the “bad faith” part. The good (and bad) thing about it is that it's a rather subjective decision as to whether a name was registered in bad faith or not. As result it is not always a clear cut yes you can do this, or no you can't. But overall cybersquatters almost always loose the name, while reverse hijacking is quite rare.
