People look smaller and younger, even when you haven't grown since 7th grade
You prefer to socialize with adults
Your email inbox is not full of messages from friends, but from various organizations, colleges, and people reminding you to pay for housing
You read more nonfiction than fiction
People who left to serve two year missions two years ago are home. What a concept.
You print out calendars to plan our your week, or month's, meals.
You make more business calls than "let's hang out or talk" calls
Your friends are starting to get marrried. And have children. And retire. Oh wait, not that last one.
The "in five years..." talks are sounding less and less like the previous five years.
Your calendar gets used more than your wii.
You start to lose your hair, and then you realize that's just from stress.
You do things to remind yourself of childhood, like buying crayons.
You know that you only have a few more birthdays before age...