Wow, I'm taken aback by this, in a good way. This is _such_ a great idea and useful tool! Very well executed too, if I may say so myself. I've been playing with it a bit and I can't even come up with anything substantive in the way of constructive criticism so far. That's coming from someone who's been a Nginx advocate for quite a while; talking about it at conferences, etc.
Julia, if you read this: Remarkable work! Based on the comments here, I'm late to the party but I'm glad was bored enough to come here and stumble across this tool and your blog!