Crimson Room and Veridian Room were created by fasco-cs.com as shareware and ask for a donation if you enjoyed the games. Both puzzle solvers are point and click, and involve some intricate puzzle solving skills. The games can be played in both English and Japanese. The idea is that you are stuck in the room. You have to solve the puzzle to get out. You leave the Crimson Room and end up stuck in the Veridian Room. Each room is viewable, but un-enterable, from the last. Very creepy, but very cool.
You need flash and shockwave for these games.