Since Mozilla is a globally distributed project, I work with people in many different timezones. When I want to chat with someone, I often want to know what time it is in their local area. Profiles on mozillians.org now show the person’s local time.
Even better, if you hover over the time on the profile, you will see how many hours that person is ahead or behind you. The site uses your browser’s current timezone for that calculation, so as you travel, the timezone difference will update. And that’s quite handy for a bunch of mobile Mozillians.