Web Performance and QA Tools?

perf_monkey asks: "I'm part of a large Web Infrastructure Quality Assurance (QA) team at a large financial institution. Currently, we use Mercury Interactive's LoadRunner like a bunch of trained monkeys. We also use QA Load and SilkPerformer, but for smaller (non-J2EE) projects. As one of the technical folks, I've been trying to expand our horizons and our budget. I can no longer believe that large companies are willing to pay a QUARTER OF A MILLION dollars for the privilege of an additional 2000 Mercury VUsers. I'm looking at both commercial and open source alternatives. I've been tinkering with The Grinder and have had pleasing results. While not a full-blown QA tool, it is an excellent 'programmer's' load test tool. I was hoping that there are other tools like this and was hoping for the community's opinion. What web performance tools do you use and what do you think of them?"