Tools for Stress Testing Websites?
rickindy asks: "What do you usedfor web site load testing tools? Open source or commercial is fine, but my employer it hosting a boatload of sites, and we would like to find the breaking point for the server at some time other than 3:00am."
I think this link can be helpful for you, it provides a huge list of web test tools. They are organized in categories for which sort of test one would like to perform. They also have a FAQ which answers several questions about how sites can be tested, and it also points out what things you should think about, like; what are the expected loads, who is the target audience, what kind of performance is expected on the client side, and so on.
2 reptiles beneath your current threshold.
http://www.acme.com/software/http_load/
There's the Jakarta project's JMeter, from the folks at Apache. It's written in Java, but can be used to load test a wide variety of network resources.