SummaryEver wanted to send secret messages to you friends and easily decode them.. Well here is a simple decoder ring to do it.. built using under 2m of filament. All you need is an understanding of Caeser cipher and your away. http://en.wikipedia.org/wiki/Caesar_cipher InstructionsPrint out all three pieces and then put the little ring on the big ring and glue the cap on the top.. you may need to sand down the cap slightly so the inner ring moves more freely.