Amazon.com has 84-Count Maxwell House Breakfast Blend Coffee K-Cups on sale for $20.69 ($18.26 w/ 5+ S&S) when you clip the 10% off coupon on the product page and checkout via Subscribe & Save. Shipping is free.
~$0.24 per K-Cup w/ 5% S&S
~$0.22 per K-Cup w/ 15% S&S