Quoting JNR:
Only 1 sextillion dollars? Cheap. I'll raise you to 3.8 centillion /ubbthreads/images/graemlins/tongue.gif
Check on limitations with collector plates, if you plan to drive it more than a couple thousand a year and/or beyond what they deem "special" events. Varies by state, but sometimes they are restrictive.
In WA they limit it to pleasure driving, special events, etc.
Basically no for-hire use, and no general transportation, though if you daily drove it to work a couple days a week, I doubt anyone would get wise.
The fact that you never have to renew tabs makes you emissions exempt essentially, and you get RETARDED cheap collector insurance. They'll be stricter on mileage limits than the state anyway.
WA limits it to vehicles 30 years old and older, so I have an inquiry in with them as to whether or not there are any exceptions, assuming for instance paperwork detailing rarity & whatnot.