Secret Message Websites
Clue / Cluedo : TheArtofMurder.com - A collector's look at the world famous detective board game.
Clue / Cluedo... a look at this colorful mystery game and its spin-offs throughout the years.
4,510,781 
$ 240.00
Self-Destructing Message [ DestructingMessage.com ]
Create a message which will self-destruct when the recipient reads it so it can never be read again!
1,166,233 $ 720.00
CipherPrize Challenge
Free cryptographic puzzles; no registration required. Ad-free, non-profit site featuring puzzles for prizes. Use the image to solve for a password that unlocks the prize vault. Difficulty level: Very challenging. (Annie Kaune)
2,055,099 $ 240.00
Secserv.me - anonymous chat, secure messaging and sharing encrypted files
Without registration and personal data, but with functionality and data encryption enough for your private conversations
1,071,916 $ 720.00