While still in Camelot, go to the treasury room. Type "ham and jam and spam a lot" (no quotes of course)
At the docks, type "look name" at the ship and the game will respond with "It is Greek for Kristi". Then type "look kristi" and the game will reply with "Peter loves Christy and Christy loves Peter and that's all you need to know." It is a clear reference to Christy Marx and Peter Ledger.
A message at Stone Circle says something different than it Merlin's translation for it.
On a Roland MT-32 connected to your machine and selected as your MIDI device. This works on some of the MT32 emulators as well (such as the information box from Dosbox). The display on the Roland shows several messages, including:
'Conquest of Camelot'
'(It's Only A Model)'
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