Can the browser selectively request resources from a website?

I'm trying to dissect some well designed sites, in order to learn more about unobtrusive JS. One problem I am experiencing is that one technique for unobtrusive/graceful degradation seems to be loading a base HTML page and heavily modifying/appending e开发者_如何学编程lements with JS.

It would be good if there was a tool where I could just selectively load scripts and html resources, so I can more easily see what is modifying what. A great tool would be something like Chrome's resource window and I could right click on a resource and select "don't load" or something...

Thanks!

PS. if anybody has sites they recommend me take a look at, MUCH appreciated. I'm just checking Fanbase.com right now

You could use a Fiddler filter to prevent a URL from loading.

You can also use Firefox's Web Developer Toolbar or IE8's Developer Tools to disable CSS, images, and/or Javascript.

Or you may want to check out googles http://code.google.com/speed/page-speed/ which will show you exactly what js calls and where.