Every now and then you come across a piece of software that is really incredible. I was originally blown away when I first used a Video Toaster on an Amiga 2000 (OK, I know, that was hardware and software....but c'mon, it literally was the start of the desktop video revolution we all take for granted now) . I also played around with the then free add-on tool called Lightwave.
Since my roots have always been in video production, I always am fascinated in how far software has come. Enter Wirecast a little gem that is truly an incredible piece of software for those on the spot video production needs without having a huge video rig. They also produce an appliance now as well as still selling the software standalone.
Wirecast allows you to connect multiple cameras via Firewire, USB, IP, and NDI mix in pictures and movies, apply lower third graphic overlays, manipulate sound and use some PIP effects and move seamlessly from one to another. You can apply video effects and green screen.
The product is available for Windows and OSX and not only allows you to record locally as you live switch between all your composed "shots" but also STREAM the event live in Windows Media format (Windows Only), Flash, h.264 and Quicktime. You can do push or pull streaming and also stream to relay servers or outside services like Eastbay Media.
I have used Wirecast on many occasions as a front end to video conferences and quickly apply lower thirds etc etc.