Mozilla Evangelist
Looks like I was able to convert the guys on my team at work to using Mozilla as their primary web browser. It all started when one of the guys complained about those annoying pop-up ads and I couldn't help but gloat that I never get any. I told them that I was using Mozilla and I was a little surprised that they never heard of it. So I directed them to the site, and had them download it.
After that I showed them how to set up their preferences to disable popup/under boxes (Edit -> Preferences -> Advanced -> Scripts & Plugins -> uncheck "Open unrequested windows"). I also showed them how to hide banner ads, which is another built-in Mozilla feature (right-click on the image and select "Hide images from this server").
While I was at it, I showed them one of my favorite features – tabbed browsing. What that means is that you can middle-click on a link to have it load up in a separate tab, in the background so you can still read the current page, instead of having multiple windows taking up space on the desktop. (Edit -> Preferences -> Navigator -> Tabbed Browsing -> check "Load links in the background" and check "Middle-click or Control-click of links in a web page").
After demonstrating this really handy feature, it didn't take too long for them to make Moz their default browser. Score one for the good guys. =)