Bigstring.com 4

Bigstring's weakness is in it's ability to manage incoming mail as it lacks the ability to sort and filter when compared to other services I've used and it's user interface is a little clumsy. But it does have some novel features for outgoing mail. It allows you to track and edit messages after they've been sent and has a fun customizable self destruct feature which is something I haven't seen available anywhere else. If you purchase a premium account you get extra features like video email and pop3 access but I've only used the basic free account so I couldn't tell you if it was worth the cost or not. But the free account is totally worthwhile as far as I'm concerned, being able to send a message that will burst into flames after it's read is just too fun to pass up.