Browser-based here means the browser has the complex duty of delegating all control to the Flash plugin.

I actually thought you were talking about this: https://www.circuitlab.com/

I just came across it the other day, and though I haven't played with it a ton yet, it seems like an extremely useful tool for learning about electronic circuits.

That is the best online schematic tool I have ever seen, hands down. Bookmarking now.

It's in flash, duh. (I don't mean to sound like an asshole, but nowadays something done in flash is not something done in the browser)

Also see: http://falstad.com/circuit/ (Java applet)

Another one: http://logic.ly/demo/

Company I work for also just soft-launched http://www.partsim.com into this space about a week ago. No browser plugins needed I believe.

Delightful. I made this!

http://www.neuroproductions.be/logic-lab/index.php?id=9342

Cool, now i'm a gonna try and reduce the number of components to do the same ...

Its a interesting site :) However I couldnt figure out how to connect one output to two inputs.

Look under the "Extras" category. There's a 1 to 3 "splitter".

So.. it's like a nerfed version of LabView