Something with more than 3 gears? Modern transmissions have a lot more going on inside that that. I understand that the concept is somewhat similar.
The biggest thing for me is that I've simply never seen anything like what is being shown in that video (as far as synchronization). It's probably the same principle, but the parts look alien.
I remember building an old GM trans (four speed) where there was a removable top cover that basically worked about as well as having a 'cutaway' type trainer...trying to find some pics of that.
edit: this article has some good pics.
http://www.highperformancepontiac.c..._speed_transmission_rebuild_pt2/photo_06.html
You've got the synchronizer hub, with the synchro sleeve that slides back and forth across it (that's the part with the groove that the shift fork slides over. The synchro sleeve pushes on the blocking ring (bronze colored part with small teeth), which in turn pushes against the gear. The gear being the part with the big constantly-engaged helical teeth; but those aren't the important part. The bit that actually engages the gear are those attached 'dog teeth' (part of the gear, not removable) which the synchro sleeve slides over to engage the gear.