I handed in my resignation this week.
I've had many jobs over the years and I've quit them all, sometimes in less-than-professional ways (e.g. sending a cowardly email following exactly one day of work). Even on the few occasions where I gave proper notice, I hastily dropped my "I quit!" letter on the boss's chair and then scurried home, postponing the awkwardness to the next morning.
I'm 35 now, and I've been at my current job for nearly five years. A hit-and-run letter wasn't going to cut it this time. So I marched upstairs, closed the office door behind me, and asked my boss if he had a minute. He did.