Ages ago, Love snuck an addon into my addon folder (something he does occasionally when he thinks my UI needs some "help"). It was a very small, very simple addon. So simple in fact that I've never had to update or change it in any way through all the years I've had it, it's always worked. And it only does one thing. Whenever I log on I get a huge poster in the middle of the screen that says "I Love You!" and one of the sounds from Love is in the Air holiday.
Logging in on any other computer means I don't get this poster smack in the middle and no sound, and it feels really... wrong. I've become so accustomed to it always being around that I don't like it when it's not there. And I don't even look at it anymore, I just click it away with a reflex and go about whatever I logged on for, but I still always notice when it's not there. And every now and then, I stop at it and remember why it's there. That it's been there through every change and everything new - something familiar and safe. I look at it and smile. The smallest, yet maybe most important of my addons.
Today Love and I celebrate 6 years together!