.htaccess Explained

Well, I'm not going to explain it, I'll leave it to this site. They provide a brief, clear but comprehensive explanation of what .htaccess can do for you and provide good examples in each case.

Topics include:

- Error Documents
- Password protection
- Enabling SSI via htaccess
- Deny users by IP
- Change your default directory page
- Redirects
- Prevent viewing of htaccess
- Adding MIME types
- Preventing hot linking of your images
- Preventing directory listing

Update: Here's another tutorial (please ignore the spelling errors)