For example, Tim Berners-Lee's WikiName is TimBernersLee.

Your name is also a potentially valid WikiWord when used within a topic, however the home pages of registered users on this site are stored in the TWiki TWiki web. Prepend  TWiki. when you sign your username in a topic - write TWiki.TWikiGuest to link to TWikiGuest, your personal topic page in the TWiki TWiki web. This will ensure that your personal topic page is linked to at it's location in the TWiki TWiki web. For convenience, your signature is also provided to you for copying and pasting when editing a topic.

Though rarely used in common practice, you can use the special %MAINWEB% variable to prepend to user names, for example, %MAINWEB%.TWikiGuest.