B&H Photo-Video offers the X-Rite ColorChecker Passport for Windows or Mac, model no. MSCCPP, for $99. (Click through "B&H" to see this price.) Coupon code "PSWBH15" cuts it to $59. With free shipping, that's tied with our May mention and the lowest total price we could find by $23. It functions as a white balance target, creative enhancement target, and color control target for post-processing consistency, while the balance card enables reflected-light meter calibration.