Open 2.4GHz RFID project is free design of active RFID device. Device has it own unique serial number which allows to identify it among others. Also device may have additional information that can be read. OpenBeacon can transmit and receive radio signals what allows to use it for variety purposes like tracking, and remote control.
Open beacon heart is Microchip PIC16F684 microcontroller with Nordic Semiconductors 2.4GHz NRF24L01 front-end chip. Transmitting range of beacon indoor reaches up to 25 meters. And 80 meters in open air. There is only beacon tag and USB reader circuits and firmware available freely. USB reader is built under AT91SAM7S123 ARM7 microcontroller which firmware can be compiled with GNU ARM-GCC compiler. Project authors says, that the next step would be to change the current node CPU (PIC) into an ARM based microcontroler with USB connection and the possibility to use GNU C/C++ compilers for programming issues. Also with small software modification at least two tags could communicate to each other without the need for base stations. Well seems like nice project to stick with.