sneakemail.com
a followup on the previous post, anyone who wants a spam-free inbox should really look into this sneakemail thingy.

how does it work? [+]
effectively it allows u to create an unique email address (on-the-fly) that can be used for signing up for freebies, we all are suckers for "free! registration now!" stuff.

e.g.
i need an email to sign up with XXX site. qwerty@sneakemail.com is created with [XXX] as the label. any emails that comes from XXX site, will be sent to qwerty@sneakemail.com and in-turn forwarded to your personal email address. however, sneakemail will append the label [XXX] to the incoming address. that way, u know exactly who has "sold" your email address when u receive your 541st "be the bigger man in 6 days!" SPAM. and when reply to the email, sneakemail will remove the label and send your reply with qwerty@sneakemail.com.
you can then choose to stop all emails to qwerty@sneakemail.com or allow only emails from a certain domain....etc


pretty cool stuff, takes a tad of extra effort to create an additional email for each sign-up, but it's well worth it.....
and did i mention it's FREE!?! (donation-based service)