That cryptic sign, the »¿ is a BOM - a byte order mark. This is set by some text editors, if you encode your page as UTF-8. Most commonly Microsoft Editors like Visual Studio or Expression Web add this BOM at the beginning of your page. You don't need it with UTF-8, only with UTF-16. UTF-8 is recognized by most editors automatically. Also W3C Validators throw error messages if you encode your UTF-8 page with a BOM.
To get rid of the BOM in Microsoft's Visual Studio 2008, go to "File" -> "Advanced Save Options" and choose "UTF-8 without signature". There you go no more cryptic »¿ signs at the beginning of your Web pages.
This is also discussed by the guys at the Microsoft Silverlight Forum
If you use Linux or MacOSX, you only need the old school editor vim
:set nobomb :wq!
The first line opens vim. The second enters into command mode and removes any present BOM. The last line write, quits and enforces these two actions on your file, just in case its write protected. Or you do this all without opening vim by using the command switch.
vim -c "set nobomb" -c wq