Bed Bath & Beyond offers the Bar Keeper's Friend Cleanser and Polish 21-oz. Canister for $1.99. Opt for free in-store pickup to avoid the $5.99 shipping charge. (Lowe's offers it for the same price, with stock varying by ZIP code.) That's $3 under the price you'd find at a Williams-Sonoma. It cleans tough stains, including lime and rust, and shines pots and pans made of stainless steel and copper.
For in-store pickup only, Home Depot offers the Rubbermaid Disposable 12x12" Microfiber Cloth 20-Pack, model no. 1887909, for $1.88. That's $0.09/cloth, $4 off list, and the lowest total price we could find. These 12"x12" cloths purportedly remove 99.9% of microbes.
Fry's Electronics offers the iRobot Braava 380t Floor Mopping Robot for $239.99with free shipping. That's the lowest total price we could find by $60. This cleaning robot dry and damp mops hard surfaces and tracks where it cleans to ensure complete coverage.
Update: It's now available for in-store pickup only.