Just give a website address that displays a rotating physical address in Russia or China. Rely on the free PR from all the news stories about how terrible it is to scale with minimal "marketing" costs.
If you picked the right districts, it wouldn't even cost that much to tilt the votes in your favor. At $50/ballot you'd almost certainly get 11,000 extra votes in Michigan - enough to swing the state in the last election at a total cost of just over half a million dollars.
This ease of abuse is one of the many, many reasons that I support a single, national vote for president over per-state winner-take-all electoral college voting.