I wanted to look for low-hanging cams (default l/p combos) but was too annoyed at all the fucking typing I'd have to do. After playing with a few methods to simplify this, I found the very handy AutoHotkey program, which has a scripting language, and wrote a script that tries the 3 basic l/p combos on the URL that is currently in the clipboard.
http://pastebin.com/x57gK7LDInstructions are included in the comments of the script. Basically just download AutoHotkey, paste this script in, save, reload the script, and now you can use Win+Z, Win+X and Win+C to automatically open a new tab and try the default login/password combos. Tested with Firefox and Chrome.
Recommend you also get a link grabber such as Link Gopher for Firefox. Pic related. Makes life a lot easier. Just triple-click a line, ctrl+C, then win+z/x/c to try out the defaults. ezpz.
Note that this will not work on cams that don't use the standard HTTP login form. Windows only, too, sorry.
If this helps you, consider tossing me a cam you find using it. I haven't been on IRC yet, but, uh, yeah, I probably will be eventually, heh.