An ARG without puzzles has a tendency to confuse players. Really it's just an interactive narrative without them, and good ARG is about giving the players something to do. Here is a fun little archive of some of the old Deus City images that were used for the daily news from the future. A few of them are actually old puzzles that are still quite solvable. With that game, our goal was a consistent "Neo Retro" tone that mixed the apocalyptic dystopian imagery of 2036 with the iconic Art Nouveau of the 1930s and '40s.
In Electron Innovations we took a much different approach, with the main game page being very am-pro, but the puzzles having a very strong and consistent aesthetic 'from the cube' designed by our team of students. Below are the (normal) puzzles from the game as well as a bunch of unused, early, and rough ones. Many of the solves are now available only on the player forums and our now unlocked ARGlab dev blog.