Like everyone said. No information needed to sign up. Been using it for over a month, and only one site had blocked mailinator - it was Goodyear as I looking at some items on their page (LOL).
In regard to everyone being able to access a mailinator account, I think that, in a way, this also provides security. Because why would a spammer or con artist want to waste time sending mails into this massive void that won't reach 70% of its users?
The mail doesn't stay in the inbox long before the site deletes, and people won't use this for personal items, so automatically, these spammers junk has a 70% chance of being dumped. People might go weeks without checking it, yet continue to use it confidently. Spammers: the joke is going to be on you someday.
Over the years, I've changed emails a number of times because, even though I wasted countless hours unsubscribing, I still got emails from them or from other companies they probably sold my address to. I love mailinator! As long as they keep up this minimal, excellent service, I will be your fan.