The one I hear most about is SnapperMail, but the versions with SSL are between $49.95 and $59.95. And you can’t download the manual to see exactly how it works unless you’re already a customer. If there’s one thing I’ve learned, it’s to READ THE MANUAL before buying.
But in terms of value, Agendus Mail SSL Edition, at $24.95, is a better deal. And with the manual, I can confirm that it handles an unlimited number of wireless e-mail accounts but only one hotsync account. So if I decided that I really, really wanted to get POP access on Yahoo! or use my Gmail account, I could do it this way for $24.95.
All told, I’d rather stick with VersaMail, but since I can’t get an updated version with the SSL, if I want to use my main e-mail account with the Palm, I have to get one of these “extras.”