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Rather than a Propeller based Arduino killer board, I would like to see people replicate these "awesome" arduino projects being shown on Hackaday, MAKE, Instructables, etc, etc, with Propeller based versions. There are so many projects done that get all sorts of attention and most of them could be done with a Propeller without breaking a sweat. In fact, some recent projects shown on Hackaday as some "new" idea have been done with a Propeller years ago.
One was the M&M sorting machine. That's old news for a Propeller project, but apparently is an eye-opening, jaw-dropping idea for the Hackaday folks. Another are the numerous Reverse Geocache type projects. Several Arduino ones are on Hackaday, many without sharing their code, yet no matter how many times I submit my Propeller based one with all of its code and design, it never makes it to the blog.
So, next time you see some attention-getting Arduino project, embrace it, learn from it, then duplicate it much more beautifully with the Propeller and repost to Instructables, the forums, etc, etc. Then post comments on the Arduino version and link to yours.