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Shameless self promotion: there is also my http://tempalias.com which doesn't require you to create an account, or even just visiting the site more than once (there is a bookmarklet).

Also, the full site is open source (node.js), so you can run your own at your own domain

I use Sneakemail: https://sneakemail.com/

It has lots of options and tweaks available.

Shameless plug:I made http://www.pepbot.com it's a temp mail service with the ability to automate the confirmation task that many services require to verify your email.

I use http://www.dispostable.com/ for my throwaway mails.