This is a screencast to demo how one can stream audio from multiple sources at once using Rogue Amoeba's Audio Hijack Pro (rogueamoeba.com/audiohijackpro/) and Cycling'74's Sound Flower (cycling74.com/products/soundflower). As an example I use UStream.tv (my personal favorite streaming platform).
I used ScreenFlow to make this demo.
Audio gear: Alesis IO|14, Focusrite Voicemaster Pro, Heil PR-40
Special thanks to the awesome music made by Brad Sucks. Check out his site at bradsucks.net