Cyberairlines.net
That's what I'm playing. It's a bit more than log on in the morning, lunch, evening thing like Trukz is. You have to send your airline fleet out and land them when they are scheduled to land. You can leave them up in the air and they don't just circle using up fuel, but they don't make money until you can land and take off again either. Thus, the planes fly in real time, but you don't necessarily have to get logged in at the time they reach the destination to have the flights paid for. You do have to wait in real time before you can land them though.
I'm Nighthawk on both Trukz and on Cyberairlines driving for Colossus Freight and flying for PanAmerican Airlines.