For Prime members only, Amazon offers the Sparkle Pick-a-Size Giant Roll Paper Towels 24-Pack for $21.81. Order via Subscribe & Save to drop it to $20.72. With free shipping, that's essentially tied with our June mention (which saw an 8-pack for $7) and the lowest per-roll price we've seen at 86 cents each. (It's also about a buck less than you could expect to pay in local stores for this quantity.) Each roll contains 107 sheets.
Note: Be sure to cancel Subscribe & Save once your order ships or you'll be billed for subsequent shipments.