This library was written because, in my opinion, the Arduino's implementation of the SD Card File class is borked in that: FILE_WRITE is actually a file APPEND. WTH? If I open a file for writing in ...

This zip file contains everything necessary to adapt the Arduino libraries to the target board or chip.

A build-it-yourself, 6-wheel rover based on the rovers on Mars! - nasa-jpl/open-source-rover ...

Arduino: this hardware/software combo allows you to program chips and test them on the fly—a real advantage of open hardware. One of the wacky creations possible with Arduino, this spider-like robot ...

[Chris Hulbert] is making it easy for Arduino users to program MSP430 chips with a header file that allows you to compile Arduino sketches for the Launchpad. This makes sense, as the growing number… ...

Arduino unveiled a new preassembled board today, one that includes a variety of sensors and controls already assembled, allowing aspiring game programmers to quickly and easily get up and running ...

So just like with open source software, people can and do make derivatives of Arduino boards or entirely new products powered by Arduino technology. Why is openness important in hardware?