[font='Font family']Text[/font]
You can use this bbcode to change the font family of your text. Theoretically any font family can be used. It just won't be displayed everywhere, because every user reading your text need this font to be installed on his local machine. Thats why there is only a limited choice:
Text in [font='Impact']Impact[/font] and [font='Comic Sans MS']Comic[/font]
Text in Impact and Comic