I've been playing around with webpagetest.org for the last hour or two and the results are really quite good (in other words, there were a lot of optimizations that I overlooked).
For instance, here is HNs report: http://www.webpagetest.org/result/090808_21KF/1/performance_...
(not sure if that link works when published), it suggests that HNs .css files do not have their cache headers set properly.
Also, install yslow for firefox: http://developer.yahoo.com/yslow/
1. Let’s make the web faster (by Google): http://code.google.com/speed/articles/
2. Implement the recommendations at WebPageTest – http://www.webpagetest.org/test