Linus talks about Apple laptops, Linux distributions, his work
You know, it's not in the same class as a macbook air, but my Thinkpad x61s has been my tiny performant champ for 4 years now.  Roughly the size of the netbooks of the time, but tons more power than a netbook and the initial macbook air means it's still powerful enough for anything I throw at it.  The one bummer has been screen resolution, but I still get 6 hours battery life on it (I did have to replace the battery once), and it was just a bit over three pounds with the larger battery.