[nickray]

Regarding your second question, I suggest reading this classic article by Leslie Lamport: http://www.google.com/url?sa=t&rct=j&q=&esrc=s&#...

[jbert]

Thanks, that's a great paper (above link is timing out, I got it from this page):

http://research.microsoft.com/en-us/um/people/lamport/pubs/p...