It was too annoying that i was not getting Deja Vu Sans Condensed font for firefox itself, whereas this font is working with other applications in Gnome. I was getting Sans font instead in Firefox. After gooooogling (too long) i got a workaround for this.
Just add this lines to userChrome.css (create a new file if it is not there), create this file in ~/.mozilla/firefox/(profile)/chrome folder.
* {
font-family: “Deja Vu Sans Condensed”;
}
Before:
Firefox with Sans Font - Looks Ugly
After:
Firefox with Deja Vu Font Working - Looks Good
I love this font 
For storyline please read this : http://www.jasonlefkowitz.net/blog1archive/2007/02/howto_pretty_up.html
