Check your emails for "get up to 50% off your next order". I got a bunch and one was 50% (most are 10 or 20%). It's supposed to be a mystery offer, but they all start with slm50 or slm something etc, so that tells you your discount.
Also, they brought their referral program back, but its only $7 off $15 instead of the previous 10 off 15. PM if you need more info.