Just got this in my email.
7TH ANNIVERSARY STOREWIDE SALE!
Fictionwise is celebrating its 7th Anniversary and we're offering big
savings on EVERY SINGLE eBook in our catalog! For a limited time, all
MultiFormat eBooks are 25% off and all Secure eBooks offer a 25%
Micropay Rebate. We rarely run a storewide sale, so don't miss this
opportunity to stock up for summer!
http://www.fictionwise.com
One of their multiformats is Mobipocket. I can also confirm that their secure mobipocket's work with the recently released iLiad Mobipocket Viewer as well.