The highest capacity SATA drive you can install in your laptop - for now.

I installed the Western Digital Scorpio WD2500BEVS SATA hard drive in my MacBook computer about three months ago and tripled the amount of storage I have available. With its Serial ATA (SATA) interface, it's very simple to replace a hard drive. There are no jumpers to set, and you just have to unplug the old drive, and plug in the new drive, and you're ready to install your operating system. I had a harder time finding a small screw driver to open the hatch to the compartment for the hard drive than I did replacing the drive.

When you buy the Western Digital Scorpio drive, you may want to buy a small USB SATA drive enclosure at the same time. They're not expensive ($20 - $30) and the make changing hard drives easy. Install the new drive in the enclosure, and backup your laptop's drive to the new Scopio drive and make it bootable. Then move the Scorpio drive into your laptop and you'll be ready to go. Move your old laptop drive into the SATA enclosure, and you'll have a handy spare drive to do backups, or store documents and photos to.

Western Digital claims that the Scorpio 250 GB hard drives uses new technology to make the drive very quiet. In particular, they vary the power used to move the heads over the discs so there's very little noise from the heads moving across the platters even when there's a lot of seeking going on. Western Digital also claims that this technique of moving the heads uses less power, and it may slightly increase your laptop's battery life.

Currently, (December 2007) the 250 GB Scorpio is the largest capacity 2.5 inch drive you can buy for your laptop. Given the constant improvements in storage technology, I wouldn't be surprised to see a 320 or 400 GB shortly, but for now, the Western Digital is as large a drive as you can get, and the price is reasonable.