Flashing roms is still pretty risky on the OUYA console – if something goes wrong while flashing, you may brick your device and there is still no way to recover it . However, the skilled developer guys over from xda-developers figured out some new tricks to bypass OUYAs non-hackability. Trooper_Max describes a way to boot custom roms from an attached usb -key.
Technically this solution works by fastbooting a custom created kernel, which looks for the android system on the usb-key instead of the build-in rom. You will have to create linux partitions on the usb key, one for data (e.g. the virtual sd-card), one for system and one for the cache. The custom kernel will boot the android system placed on the stick.
As the author of this mod says by himself this is not a very convenient method of booting and testing new builds, because you will have pretty much “overhead” – first the preparation of the usb key, rebooting into bootloader from adb, fastbooting the custom kernel, etc… But it is the only way for testing new Android builds right now. You can find the tutorial from Trooper_Max here.
OUYA published the kernel sources for the console, but there is unfortunately still no word about booting to recovery/access to bootloader. There are even people looking for fellow campaigners for a class action lawsuit against OUYA for false advertisement as being fully hackable.