I picked up a Vertical Communications 7504-10 IP phone from a yard sale a little while ago on the assumption that since it was standards-based (SIP) that I'd be able to use it with Asterisk. Browsing around with google only revealed one thread where someone claimed that you could make the phones work, but said nothing about getting into the phone in the first place. But as it turns out, it's actually quite easy to configure these phones to work with an arbitrary SIP provider.
My Ouya decided it didn't want to pair the original controller any more, so I performed a factory reset after backing up all my apps with TitaniumBackup. Then I performed a factory reset, which doesn't. It left a couple of apps behind, including ES task explorer. Upon entering the adb shell, I found I could no longer su. The fix in my case was to reinstall superuser.