I reminded my #DistributedSystems class today that DNS is a global, decentralized, eventually consistent database with a continuous uptime and client compatibility window of 40 years, and I'm not sure that they were suitably impressed.
@elb I typically use this to teach the zeroth law of distributed systems: avoid building one if at all possible. DNS is a great example, where if people are willing to compromise on global agreement on names (just like there isn't one globally agreed-upon "jeff"), then you no longer need a distributed system and can instead use something like petnames, emulating how folks refer to non-computer things (and how folks named computers on internetworks before DNS)
@migratory I actually gave that speech on Monday, I think; distributed systems are like C, you PROBABLY don't want to use it. Most systems will run just fine on a core 2 duo you found in a closet UNTIL you try to distribute them. ;-)