I fly because I'm not qualified to do anything else :-S
Coming up on 10 years of commercial flying, my most memorable moment? Years ago I did a couple of Eastcoast-to-Westcoast ferry flights in R44s when I was in Australia, those were pretty memorable. Landed in the middle of the Simpson between Birdsville and Alice springs to put in a couple jerry cans of AVGAS. I wasn't planning to shut down for this - anyone who has flown R44s before knows they can be a bitch to start when hot, and it was 43C... however the damn thing started vibrating itself into the sand so I had to stop the engine. Luckily it fired up on the second start attempt.
Interesting about this is that I was 160NM from both Alice and Birdsville, there was no other air traffic from either airport, and the desert was closed to 4WD crossings for the season. So for that half hour or so, I was most likely the only human being within a 160NM radius. Which is the "loneliest" I have ever been, lonelier than most people will ever be in there life I would guess.