Okay, so I launched something quietly today. Stella. I was planning on keeping it low-key but with the "Happy Holidays" and "Hacker News goes Christmas" posts (and colors!), I thought I could balance it out a bit with some Festivus activity. I'm not particularly qualified to promote Festivus but I'm doing my best.
In any case, Stella is a performance testing tool, written in Ruby that also supports the Java VM (through JRuby). This is a preview release (0.5.3) but it's already useful for running and comparing Apache Bench, Siege, and Httperf tests. Here's an example from the current release:
stella -a opera-10 -w 0.5 -r 25,300 -m 'MaxClients=768' -x 5 ab -c 100 -n 10000 http://stellaaahhhh.com/search?term=trooper
-a: Use an Opera 10 User-Agent.
-w: Run a warm up with half the users specified for the test.
-r: Ramp up the number of users from 100 to 300, in intervals of 25.
-m: Remind yourself what this test is about.
-x: Repeat each test run 5 times, average the results with standard deviation.
P.S. http://www.youtube.com/watch?v=wmq-JDonTpc