Jazz musician Mike Gellar runs Mike's Master Classes, an online guitar school where the teachers are great jazz masters from around the world. Students anywhere can interact with teachers anywhere - and they don't have to worry about being out of town on the day of the lesson, or about the teacher going on tour. As long as everyone has a computer and a high-speed Internet connection, the class can go on.

The classes use the MegaMeeting videoconferencing facility, which is Web-based and requires no software download. The teacher broadcasts in real-time audio and video, so that students can watch and listen as if they were in the classroom. Students can use a chat facility to ask questions. MegaMeeting also has an instant-feedback capability, which lets students click on basic messages like "speak louder" or "slow down."

Here's Mike Gellar playing a lovely Ellington tune.