Well, it looks like Skype is about to shove off. It hasn't played any kind of important roll in my life since before Microsoft bought it.
I still have the Skype 0.97 beta install I downloaded in 2003, though, for what it's worth.

Speaking of that:

Who remembers when the Skype echo test used to sound like this, before it was replaced by what I think still exists? Each supported language has it's own localized recording, but I didn't capture those.

Inspired by Skype was this somewhat iconic thing I used on my internet radio show, Things and Stuff, especially in 2005 and 2006.
@BorrisInABox Ha. I remember this series of crashes from an old sesame street tape I used to have of all things. Love that little metalic thing falling at the end
@stirlock Sesame Street and Disney both used it pretty extensively, as did ZBS foundation. Almost no one used the stereo version, though.