Myself and a friend came up with a solution slightly similar to outlaws - human rights points. When you are convicted of a crime a number of human (or constitutional) rights points are removed from (proportional to the crime) for a period. The criminal is required to decide which human rights they has to give up, and is therefore directly responsible for their sentence. Note that just because you've lost points, doesn't mean that people are free to attack your with repercussions.
A rapist might, for example, lose his right to being innocent unless proven guilty. He would have to prove that he was not guilty of rape. You don't lose the ability to defend yourself, just that the odds are now stacked against you.
* Right to free speech
* Right to bear arms (although I think that's already applied in some states)
* Right to travel (ditto)
* Right to bear children
* Right to a state appointed attorney