Here's another Newegg newsletter deal good until 5/11. OCZ ModXStream Pro 500W 80 PLUS Power Supply $36 Shipped when using code EMCKEJK76 and after $20 rebate.
I use this power supply personally and would use it again. It's modular and has plenty of connections. There are two PCIe power connectors so it can handle gaming-oriented GPUs. 80Plus, Active PFC, SLI/Crossfire ready all add up to a great supply for any HTPC also serving duty as a gaming platform. The 120mm fan is essentially never heard in my case.