Newegg has the Western Digital Caviar Green WD6400AACS 640GB 7200RPM Hard Drive for $68 with free shipping. Use coupon code EMCLVNP56 to knock $10 off the price.
Features:
- With GreenPower technology, the Western Digital Caviar Green WD6400AACS yields lower operating temperatures for increased reliability and low acoustics for ultra-quiet PCs and external drives.
- Combined with WD's IntelliSeek, IntelliPark, and IntelliPower technologies, the Western Digital Caviar Green WD6400AACS has reduced power consumption by up to 40 percent compared to standard desktop drives
- The Western Digital Caviar Green WD6400AACS features the SATA II interface supporting up to 3.0 Gb/s data transfer rates, Native Command Queuing (NCQ) and hot-pluggable point-to-point connections for optimum performance, efficiency, convenience and flexibility.
- Perpendicular Magnetic recording technology enables industry-leading capacity in existing standard form factors and improves performance by increasing data density while reducing moving parts for enhanced reliability.
Newegg.com - Western Digital Caviar Green WD6400AACS 640GB 7200 RPM 16MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive (bare drive) - Internal Hard Drives
Western Digital Caviar Green WD6400AACS 640GB 7200RPM Hard Drive $58 + FS 
