I don't remember exactly what I did on my 21st birthday. It wasn't a big deal, I had already decided drinking wasn't worth it for me, anyway. Had friends to whom alcohol was way too big a deal, knew how it had negatively impacted people's lives, and ginger ale was always cheaper anyway.

I DO remember my 22nd birthday, though ... It was less than a month before our wedding, and I was a camp counselor for a week at an elementary camp. Unfortunately, I also still has to work my "summer job" every night that week, and the two places were 70 miles or so apart. Paul came and picked me up at camp and drove me to work and back, just to be able to spend some time with me on my birthday. On the ride between works, I got a cupcake with a candle on it. And all my campers (8 girls between the ages of 9 and 12) thought that it was just THE most romantic thing ever.
My mother had already given me my birthday present - when I opened my suitcase at camp, there was a bumper sticker for my (12-year-old, piebald blue and black and maroon primer Ford Maverick) car that said "This is NOT an abandoned car."