Meritline offers two Canon CLI-221–Compatible Inkjet Cartridge 5-Packs with chip for $17.95. (Select "2 Sets" "under Buy More Save More".) Coupon code "MLCY30JN" cuts it to $8.95. With free shipping, that's the lowest total price we find by $1. (For further comparison, we saw a 8-pack with chip for $6.95 in April.) These cartridges fit several Canon PIXMA inkjet printer models, check the product page for compatibility.