Staples is offering $100 Lowe’s gift cards for $90 on their website. The offer expires on 7/25/15 or until supplies run out.
The discount is only taken off on one card, so it is not possible to order multiple cards at the same time. In the past Staples has frowned upon placing multiple orders on the same account, so keep that in mind.
As of this time I am not aware of a portal that pays out for the purchase of gift cards from Staples, however it never hurts to experiment or try.