Everyone remembers Compuserve for pioneering the GIF, but I remember when they were one of the first companies to distribute compressed audio. In 1994, Aerosmith decided they wanted to be the first band to release a single as a digital download before it was available for retail sale. They chose their single “Head First” to release, and partnered with Compuserve for distribution. As this was several years before the invention of the mp3, it was available a wav file that used a proprietary compression codec that you had to download separately. This article says it was a 90 minute download for a 3 minute 5mb song. I had a 14.4k modem at the time, my unreliable memory says that it was closer to 15mb and took overnight, but 90 mins for 5mb on a 14k line appears to check out.
https://www.vice.com/en/article/6vapxr/go-aerosmith-how-head...