Who remembers IceZmodem? A backwards compatible protocol that allowed you to play Tetris or listen to .MOD files while downloading... and if you were downloading from an IceZmodem capable host, you'd even get increased download speeds!
> IceSoft Software presents IceZmodem, an amazing
> new Zmodem file transfer protocol with 100%
> standard Zmodem compatibility and many enhancements.
> While transferring files you can chat with the
> remote user, shell to DOS, edit a text file,
> play Digital MOD file Music, or play games.
> You can even get 2 pages of system information about
> the remote computer. Sysops can view the dropfile
> to find out who is using the BBS. It has one of the
> best status displays ever and includes a Screen
> Saver. TurboTrans, a Zmodem speed booster, has
> helped to get 99% efficiency on some file
> transfers.
> This amazing protocol simply has to be seen to
> be believed! Supports Sound Blaster or DACs
> for music.