As a performer, the options are endless. You can use desktop client software (such as Adobe Flash Media Live Encoder for free or Telestream's Wirecast for some cash) to bring in any camera feed you like. The limiting factor as a performer is your internet upload speed. We recommend at least 1MB upload, and even higher if possible. This will dramatically increase the quality for your fans.
As for audio, we've seen performers bring in a stereo mix of a 48 track pro tools session in the studio. We've also seen performers play with just their built-in laptop webcam and microphone.
You can also search our knowledge base to learn more: