Amazon has the 15-pack of Gillette Mach3 cartridges for $19.52 with
subscribe and save and $3 off coupon. The deal breakdown is as follows:
Amazon.com price $26.49 - 15% subscribe and save - $3 coupon = $19.52 or
about 1.30 per cartridge
The coupon can be clicked directly from the product page when logged in: http://www.amazon.com/Gillette-Cartridges-15-Count-Blister-Sust