Since a few days ago, ScummVM also supports a few BAT- and SCN-based non-interactive demos,
namely for Inca 2, Woodruff, Urban Runner and Playtoons. The interesting thing about them is that, strictly speaking, they’re not Gob-based, but are just either a BAT file that calls a small program for IMD playback; or a small interpreter for a simple SCN script with VMD playback capabilities. Either way, they practically just consist of IMD/VMD videos.
If you find a Coktel Vision demo that doesn’t yet work with the latest daily build of ScummVM, I’d be interested in getting my hands on it. 🙂

Sparked by the resulting demo exchange and discussion in #scummvm, sanguinehearts also set up an unified hosting site for demos (which we’ve been missing) and started uploading all demos already known to the team.
Similar to above, we’d like to get any yet unknown demos for ScummVM-supported games you might have.