The AIM "Talk" Feature.

I think if you have a high bandwidth you can talk to someone with your mic and they can talk to you over your speakers. I'm pretty sure, but I've never used it. Someone explained it to me once, a while ago.

That's exactly it. You can use your mic and speakers to communicate with someone else by voice. It works pretty well (and can save on phone bills), but you need bandwidth to use it.

Bandwidth.... what is this.. bandwidth.. that you do speak of? 0_o

You can use it with 56K but it may be a bit choppy while you're talking with someone. Bandwidth is how much information can go through your internet connection (the speed of your connection).

Choppy? More like unusable. In my experience, using it over 56k turns your computer into a dedicated phone. DSL and cable work great though.