You know your med school classmates are younger than you when...

1. You know what ether smells like but your anesthesia resident has never heard of the stuff.
2. They don't remember medicine before HMO's
3. When you were born, the Periodic Table only had 20 elements
4. You got the smallpox vaccine when you were a kid
5. When you were a baby, you rode in the front seat of the family car without a carseat
6. You remember when you had the choice between "regular" and "unleaded" gasoline (many thanks to my friend Joe for this forgotten nugget)
7. You remember life before Atari (thanks again, Joe)

I'll add more as I think of stuff!