I have often thought it's be great to do a "best comments of the week" email list the same way "Kernel Traffic" did for a number of years with Linux kernel development: http://www.kerneltraffic.org/kernel-traffic/archives.html
Condensing comments down to the 5-10 gems would be very interesting. And, perhaps with the voting system, not that difficult.
I just dug a little into the HN API (https://github.com/HackerNews/API). Unfortunately, they don't publish comment ratings... :-( Unless that is changed, implementing an automatic "best comment finder" would become rather more tedious... (And perhaps even turn out to be AI complete ;-) )