Thanks, that's pretty cool.
I'm assuming you don't connect this xbox to LIVE or else you'd get banned.
With JTag, you can recover the machine from an Xbox Live ban.
Xbox Live bans are based off of your machine's unique CPU key. If your CPU key or "keyvault" gets banned, you can obtain one (from an RRoD machine), and replace yours.
Again, Jtags run unsigned code. If you know how to hex edit and go diving into C sharp ... this happens.