Popped into Boots for another No. 17 supreme shine nail polish (£3.99) and checked for offers on the advantage card machine while I was there. To my suprise there was a voucher for a free No. 17 Hide and Chic concealer worth £4.99 with any other No.17 product.
I think a nail polish is the cheapest No. 17 product you can buy to get the free concealer. Its a great concealer too with a nice neat brush for application.
Voucher said valid until June.