Registry virtualisation, protected mode IE, restricting privileges of all running programs to a sensible level...
I always find these threads interesting, especially the 'knowledgeable' windows users who think running as admin with no other protection is something to be promoted. It was a flaw in XP, and some people are determined to make it a flaw in vista. It's like not putting a trapdoor over a hole in the floor because 'I know it's there so I won't fall in it'...
It's also worth noting that one of the rationales behind UAC is to get developers to improve their software. The vast majority of third party applications (particularly games) have absolutely no reason to require elevated privileges for running other than bad coding.
Here speaketh the truth. Well done.