Newegg offers the Cooler Master 120mm Silent Case Fan 4-Pack, model no. R4-S2S-124K-GP, for $12.99. This $5 mail-in rebate cuts it to $7.99. With free shipping, that's the lowest total price we could find by $5. It runs at 1,200 rpm and features air flow of nearly 45 cfm, 19.1dB noise level, and more. Rebate expires July 7.