Implementing a voting system without requiring registration

Question

I\'d like to implement a voting system on my site, without having to force them to create an account. They would ultimately be voting up/down a piece of content which has a

Answer 1

I know this is old, but just came here and had an idea..

What about something like https://panopticlick.eff.org ? Yet another thing one could throw in ..

(If this ever goes offline: This is a cumulative fingerprint made of the usual stuff plus + Browser Plugin Details + Time Zone + Screen Size and Color Depth + System Fonts + supercookies )