Despite their diminutive form factors, 2.5" Serial ATA hard drives actually use the same connectors as their desktop counterparts. These drives plug into standard SATA data and power cables, making them particularly intriguing options for small form factor systems. If enthusiasts are going to press mobile Pentium M and Turion 64 processors into action in toaster-sized boxes, they might as well bring along mobile hard drives to match.
Unfortunately, the connector compatibility enjoyed by 2.5" SATA hard drives doesn't extend to mobile ATA drives. Those drives require pin and power adapters to work with desktop ATA systems, which isn't quite as convenient.