>>It will only catch people who have configured their proxy very poorly.
To add to this, in Firefox if you use this: http://i.imgur.com/ajT98xC.png , Flash does not obey it. I kinda think Mozilla should put some kind of warning-text on this dialog window to warn uses that it doesn't apply to flash, silverlight or any plugins. This surprised me at first but it makes sense if you think about it. You really have to do a system-wide VPN type thing. Something like this: https://github.com/apenwarr/sshuttle will actually tunnel everything on your PC.
Careful, sshuttle doesn't route UDP, and by default does not route DNS requests either.
For Firefox, I don't think they should bother anyway, the world is killing flash, if you want to be anonymous on the internet use noscript and don't install flash in the first place.
Hmmmmmm..... So from what I gather here, if the ActionScript is using the regular getURL[1] that call is passed to the browser and will be proxied. But if flash tries to open up a raw socket[2] on its own, it won't know about the proxy and will just fail(or reveal your true IP)
To add to this, in Firefox if you use this: http://i.imgur.com/ajT98xC.png , Flash does not obey it. I kinda think Mozilla should put some kind of warning-text on this dialog window to warn uses that it doesn't apply to flash, silverlight or any plugins. This surprised me at first but it makes sense if you think about it. You really have to do a system-wide VPN type thing. Something like this: https://github.com/apenwarr/sshuttle will actually tunnel everything on your PC.