New York--Yahoo! will begin charging for e-mail forwarding features in an effort to create an additional revenue stream amid an online advertising slump, according to a report Friday in The Wall Street Journal. Starting April 24, the Sunnyvale, Calif.-based company will charge $29.99 a year to users who access its e-mail service through outside applications, such as Eudora or Microsoft's Outlook, according to the report. Yahoo! will charge $19.99 to users who sign up for the forwarding service before April 24.