supports FAT16 and FAT32 file systems
It doesn't support bootloader 1 wire optical interface, so it is useless in many real applications, where MPU comes flashed with tiny boot loader and only 1 wire is needed to reflash MPU with latest software update.
It is only gadget maybe good for mainstream "Beduino" - I meant Arduino fans
For me it is useless-I use DIY AVR programmer in DAPA mode connected to LPT port of 128MB RAM DELL laptop
and.. it is fine to quickly flash AVR MPU with tiny boot loader-then use 1 wire to upgrade MPU software in circuit when needed
Messing with 6-10 pins on PCB just to reflash MPU... it is hopeless