PS: That's why your Thunder on the Border thread is so important. FRegards....
I'm still trying to puzzle out how I'd pull off the "just vanish from the accident" trick-- in our state, you have 30 days to get a license plate. Most people just write "tag applied for" with the purchase date, on paper, some dealers give you a temporary paper tag- but far as I recall, none of that has any legal meaning. If the police stop you for no tag, they comfirm that you are within the grace period, and let you go. Assuming you have a valid DL, and insurance... but again, in this state your insurance on the old car has a period of grace to cover a new vehicle for a while until you get a new policy...but...
In theory, you could buy a cheap car for cash, drive it for up to a month, then abandon it, without leaving an easily tracable paper trail.