Cyptograma has to be the most appealing interface to a cryptographic puzzle that I have ever seen. The game features quotes and phrases to decrypt from famous people, and are available in either English or Español. Each puzzle is in the form of a simple substitution cipher in which each letter of the phrase is substituted with a symbol. It is up to you to figure out the letter that each symbol corresponds to.
Can you torque the talk? In this unusual Flash adventure game your spacecraft crash lands on an alien planet, and to escape you must observe the culture and learn a new language to communicate with the inhabitants of this alien world. Remarkable in its originality and design, as well as its gameplay.