I found a good deal on the 2.5" HDD today when I want to get one for my new enclosure. Although it is 4200rpm, it brings less heat to me. It is made by Hitachi and gives me 3 years warranty.
$69.99 shipped
linky
Features:
High max areal density of 34Gbits/sq. inch, up to 20GB of capacity per disk
Drive Noise Suppression System (DNSS), Fluid Dynamic Bearing (FDB) motors on all models
Fast Ultra-DMA 100 2.5-inch mobile hard drives
Antiferromagnetically-coupled (AFC) media on all models
Operational shock rating of (200Gs/2ms) for a 2.5-inch mobile hard drive
3 Years Warranty
Specifications:
Capacity: 80 GB
Rotational Speed: 4200RPM
Buffer: 8MB
$69.99 shipped
linky
Features:
High max areal density of 34Gbits/sq. inch, up to 20GB of capacity per disk
Drive Noise Suppression System (DNSS), Fluid Dynamic Bearing (FDB) motors on all models
Fast Ultra-DMA 100 2.5-inch mobile hard drives
Antiferromagnetically-coupled (AFC) media on all models
Operational shock rating of (200Gs/2ms) for a 2.5-inch mobile hard drive
3 Years Warranty
Specifications:
Capacity: 80 GB
Rotational Speed: 4200RPM
Buffer: 8MB