Yahoo now has something they call Address Guard:
http://help.yahoo.com/help/us/mail/plus ... index.html
It's not exactly the same as spamgourmet. They assign you a basename and then you can make up to 500 dynamic addresses of the form:
Basename-keyword@yahoo.com
Email is passed through until you disable the account. Also if you stop paying for the premium service, all the incoming mail is refused.
Hopefully this won't cut into spamgourmet's bottom line too much (ha ha).