Your stated goal is to debug your device using Xcode without paying Apple $ 99:
Assuming this is for quasi-formal learning purposes, and you can find a university co-teacher to sponsor you or do some kind of focused research, you can try iPhone Developer University .
It's free, but I guess the required hoops and time will make $ 99 / year for a regular program seem pretty reasonable. (I think the same goes for any jailbreak solution, but I remember what it feels like to have neither a salary nor any competing requirements in my time).
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