The (royal) seat cushion is normally $79. Free with the purchase of any Purple mattress while supplies last.
Obviously you need to 1) be in the market for a new mattress and 2) want a Purple mattress but we were getting one anyway and I called in and they honored the deal for me.
Banner on top about free cushion and adds automatically when you put a mattress in the cart:
They have great reviews and are supposed to be awesome. 10 year warranty and 100 day money back guarantee.
Was already pumped for a new mattress and this just sweetened the deal a little bit.