Ask HN: Hacker News effect - maximum page requests per second?

I'm creating a website and I want to stress test it to be confident that it will survive the "Hacker News Effect" when it goes public. What is the maximum number of web page requests per second the server should be able to handle? (Oh and I'm thinking of using JMeter to perform the stress testing and Munin to view real-time graphs of server performance. Are there any better alternatives?)