I have a 466MHz Clamshell iBook and the Griffin iMic USB dongle you speak of. It will let you use a mic with the iBook, but I'm pretty sure you need at least a 600MHz G3 to use iChat AV (i.e. audio or video Chat). If I'm wrong, I'd sure like to know. I know someone who would be ecstatic to know they could use iChat AV for audio chat on a 500MHz G3 iMac. Dave. I am using a dual usb 500 mz ibook to ichat audio with another ibook with g4 1.2 gz . However both are using Panther 10.3 it does not work with Jaguar. you need 600 mz to video chat Larry