A QuickTime movie of Jet Set Willy being played from start to finish. The recording is at 5x the normal speed, so more of a runthrough than a walkthrough...!
It's a monster 15MB file so will take quite a while to download. You can either download directly from here or use the Coral cached version (preserves the bandwidth on this site).
(It's probably best to download the file rather than view it from the site.)
Download Jet Set Willy Walkthrough mirror (preferred).
Download Jet Set Willy Walkthrough from here.
Download the game map (516kB).