Josh Plunkett, over his blog Down Under DM, has been building the complete Tomb of Horrors in 3D using tiles and Hirst Arts molds, along with dungeon dressing models from Lady Sabelle Designs. There are spoilers within (though, to be fair, the adventure is nearly 40 years old). I've shown a couple of images below, but click on either to head over to his blog to see the rest.