OK, I'll bite and say it... ...no you can't make a credible voting or rating system without a login. It's too easy to game the system to create repeat votes v

OK, I'll bite and say it... ...no you can't make a credible voting or rating system without a login. It's too easy to game the system to create repeat votes via cookie burning, ip rotation, etc (see the other responses). Forcing someone to be logged in and then only allowing one vote per poll helps keep all but the most persistent griefers. To that end, be aware account creation can be automated and unlimited unique email addresses created from one domain. However, the difference between gaming the system by creating lots of fake accounts and gaming the system via cookie destroying/IP rotation is that the former is easy noticed within your system - assuming you have built such checks in place. It's also lets you easily remove the offending over-votes to restore calm to your survey/poll/etc.