Titanium PowerBook G4/400. That was a Christmas gift from my mom in 2001. She got it from my sister's boyfriend at the time. Nice gift, but I didn't really know what to do with it. Although I used Macs professionally, personally I was all PC until 2003.
That Mac lasted until November 2009 when the logicboard died the first time. I say first time, because I replaced the LB twice. By the second time around though it had just started to fall apart and I had other Macs. It got shipped off for parts to another user here on MacRumors. It did serve a full year as a production Mac at work though until my boss bought me a new Mac.