We will replace our square logo at Twitter (https://twitter.com/freemarker), and probably will use the same logo in the future elsewhere too.
Which one do you prefer from the *top* row (1, 2, 3)? https://drive.google.com/open?id=0B5BwTaGcWGtNLU0wQmFiUElFc2c (The bottom row is for file icons, but currently we won't use them anywhere.) Thanks for Julien Nicolas for providing these! -- Thanks, Daniel Dekany