Newegg has the Scythe S-FLEX SFF21D 120mm Case Fan (33.5 CFM at 8.7 dBA) buy one get one free. Look for the Combo Deals under the
Newegg.com - Scythe S-FLEX SFF21D 120mm Case Fan . Comes to $19.99 shipped for 2. Don't forget BCB.
This fan is known for its low noise and not air flow. Don't get it if the flow rate is the main consideration.
Same price also applies to the the
Newegg.com - Scythe S-FLEX SFF21F 120mm Case Fan (63.7 CFM @ 28 dBA) and
Newegg.com - Scythe S-Flex SFF21G 120mm Case Fan (75 CFM @ 35 dBA) fans.
To get free shipping, first add 1 fan to cart, then check and add the combo deal on the next page. Shipping charge will be incurred if one directly uses the combo deal on the product page, or purchasing more than 2 fans at the same time.
Scythe S-FLEX SFF21D 120mm 33.5 CFM 8.7 dBA Case Fan 2 for $19.99 Shipped 
