ARe regularly offer books from an e-publisher at 30% or even 50 % rebate for a limited period. That means you pay the full price, but half of the amount (or 30%) is then returned to you in the form of a gift card of sorts that you can use for other books. It's more rare that they offer a straightforward discount, but they have done so in the past.
Obviously this is fairly pointless if you only want to buy the one book from them, but if you buy there regularly anyway, as I do, it's fairly attractive. They carry a lot of independent e-publishers (not just of erotica, although you might get the impression when you first look at their site), and they have a very nifty buy-one-get-one-free program.
Right now Ellora titles are available at 50% rebate, and for the second half of January ARe have announced a 30% Harlequin rebate (not that we depend on
that right now
).