This document discusses using Amazon's EC2 cloud computing services to crack WPA2-PSK WiFi passwords through brute force attacks in a cost effective manner. Custom code was written to parallelize the cracking process across multiple EC2 instance types. Testing showed that 100 million passwords could be cracked in around 2 months for $240 using this approach. The cloud provides elastic, on-demand computing resources that can be leveraged for password cracking at low cost compared to building your own hardware.