Here is $100 credit to sign up for yahoo Search Marketing. Looks like there is no expiry on the offer.
sem.smallbusiness.yahoo.com/searchenginemarketing/onlinemarketing.php?cc=2&o=US2507&cmp=YahooSep_200 8Email&ctv=EM&s=Y&s2=EM
HINT: If opening a link above is somewhat a hassle for you then try the tool in my signature to remove the hassle forever
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