10 Minute Mail (disposable email)
10 Minute Mail
Launched to help protect innocent Internet users from unsolicited e-mail messages, this service provides a free, temporary e-mail address that expires within a 10 minute time period. If you're wary of disclosing your e-mail address to a site that requires a registration, why not use 10 Minute Mail instead? You'll be able to register with no questions asked, and (more importantly) you'll avoid being added to spam (junk mail) lists.
http://10minutemail.com/10MinuteMail/index.html