Foca is a compact USB to serial adapter equipped with BEE (20pin 2.0mm) sockets. With integrated FT232 IC, It can be used for programming or communicating with MCU applications. On the other hand, you may connect your PC to various wireless applications via the BEE compatible modules.
Here at this web page, you will see how to use the FT232 chip as a AVR writer(Bitbang) and all the software that you need for the job.
Link: http://www.geocities.jp/Arduino_diecimila/bootloader/index_en.html