iChat AV
Apple's new iChat AV is already cool as hell, even in its public preview form. Shortly after downloading it and installing it, I was chatting with folks over audio using the built-in mic on my PowerBook.
I have a Canon Elura DV video camera that gets precious little exercise, so I hooked that up, and it works like a charm. Although it seems like some manual tweaking of the bit rate comes in handy for reliable connections, I'm amazed by how well it works and how clearly the pictures come in.
It is, as usual, the attention to detail that grabs me. For example, when I started up a video chat with my friend David this afternoon, I was listening to iTunes. iChat AV told iTunes to pause, then unpaused when the chat was finished.
This is cool.