Wes Felter's discussion group is one of the most intellectual pieces of 'net property I visit. I only lurk, as I honestly don't always follow everything that's said there. Folks to listen to: Aaron Swartz, David McCusker. David's mind especially is incredibly dense. And I mean that in the nicest way – his brain, as visualized on the intellectual space-time-continuum would be like a black hole. Warning: David's weblog is a journey through a mind that does not work like yours.