Having dual monitors is great, like say watching a video in 1 screen and doing some work in another. However, if its a Flash video you can’t watch it full screen and work in another window because as soon as you click anywhere else the video restores. Well someone has figured out how to fix that. Someone that goes by d.i.z. has made some changes to a .dll file and tada, once patched you can watch a Flash video in full screen on 1 side and continue working on another screen without losing your full screen. Geek’s making the world a better place, 1 patch at a time. -Greg

You can grab the patch from the original blog:
Watch fullscreen flash while working on another screen [via MakeUseOf]