How to connect cooling fans

We have a few local used computer stores, and I was at one the other day and they had a huge box of old working supplies, including MANY computer fans of various shapes and sizes ranging from $2.00-$5.00, and old computer power supplies starting at $5.00 you guys that are interested might want to check out some used computer stores, I think I could build a decent fan cooling system using 2 fans for less then $15.00, and all the stuff comes with a 90day warranty....
 
the new 120's are quieter and move more air..some are even adjustable..hmm

I may use on of those I pikced up 2 120 adj for $20
 
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