I guess this is more of a warning than a hint. If you allow someone to connect to your computer using the "Exchange" feature in Timbuktu Pro, they have access to all documents for alll users, no matter who you are logged in as. This could be a serious security issue.
[robg adds: I don't have Timbuktu, so I can't confirm this one ... if someone can confirm or deny in the comments, I'll either leave the story as is or correct it if necessary.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20031028074620323