Nullsoft's streaming server? I ran a web radio stream for a small group of friends for a short time using it. Pretty sure the only reason I ever became aware of it was Winamp's built-in station browser. It made me wanna learn how it worked. I can't remember anymore but I assume Shoutcast must've had a "publish" type option to make them show up in the list. That stream browser also introduced me to the demoscene (there was a website that broadcast various demos) and expanded my tastes in music across so many genres. RIP to Wazee and Digital Gunfire. At least SomaFM and Digitally Imported are still hanging on.

Do you remember RipCast? Before I learned where else to look, and when #mp3z on IRC failed me, I'd use it just to be able to save those unobtainable songs. Like a digital equivalent to leaving a cassette recording the radio in hopes of snagging a few songs you wanted to keep.

It still exists. I run radio 24/7 with Shoutcast.