Eight years — basically you're a doctor of the forums.
Put a filter on it.
It's been 7 years since you signed up!
Congratulations! Big step.
Today is your six year anniversary!
You've been here for five years now.
Today is your four year anniversary on the site!
You've been here for three years, thanks for sticking around!
Hey, Happy Birthday!
You've received 5 likes -- guess you're doing something right.
You've made your first post! Welcome!
Today is your two year anniversary here.
Bold. Going a full week without an avatar?
This is your one year anniversary. Thanks for hanging around.