2001. After 9/11, I couldn't fly to NJ from LA, as I wanted to be with my family with everything that was going on at the time. I called a friend at AA, and they actually recommended National, since I'd have a better shot at a more comfortable vehicle for the loooong drive. They were right. When I got to the LAX pickup area, I was informed about the Emerald Club and due to the nature of the drive, I was upgraded from the meager "mid-size" I reserved, to a luxury SUV (can't remember, I think it was an Escalade). Kept it for 2 months, while I stayed in NJ.
Returned home to LA and have been a loyal member ever since. Now on company relo in the PHL area, and I have had a vehicle out continuously since 2005, which is when I was upgraded to EE (and then to VIP the following year).