Know of a good user agent database? Creating better robot & user agent detection

[eluser]skattabrain[/eluser]
I need to track 'just humans' for a site performance measuring tool i'm building. while the user agent class is helpful, it doesn't do what i need it to do.

So the first step for me, is getting a database of user agents, as up to date as possible.

I've found this ... http://www.user-agents.org/ - but the last entry was in Feb 09.

Anyone know of a good database of user agents? Or for that matter, how to tell the difference between a robot and human? This is a problem that needs solving. If there was a service like Akisment, but for user agents ... hmmm ...

Anyways, I thought a trick might be to try to store a cookie and if later I can detect a cookie, then I had a human ... but it's looking like many bots sets cookies.