Last night, the Video Game History Foundation hosted a superb event delving into the source code of The Secret of Monkey Island with one of the game's creators, Ron Gilbert.
The VGHF is a "non-profit organization dedicated to preserving, celebrating, and teaching the history of video games". If that's not a wonderful mission, I don't know what is. Be sure to check them out.
During the event, VGHF founder and host Frank Cifaldi turned to the topic of SCUMM-U ("SCUMM" being the scripting language many LucasArts games were built in, "U" being university). This was the training that new hires to LucasArts went through so they could understand how SCUMM worked.
He then showed some Sam & Max sprites that were created for use in that training, presumably by Steve Purcell, using the limited colours of the EGA palette.
Though we've heard mention of these sprites through interviews, this is the first time the world has seen them.
Check out the sprites in action in the video below!