For a device often called a USB "key," the tiny flash drives people carry around with them are generally not well-suited to being attached to a key ring. Most have plastic bodies, and in our experience, the plastic key ring loops inevitably break after a few weeks or months.
LaCie's IamaKey USB flash drive offers a potential solution with a new drive that is, amusingly, shaped like a key. More importantly, the entire device is made of metal, including the key ring connector at the top end.
As chronicled in this blog post, our main purpose for attaching a USB drive to a keychain is to have handy access to files. Testing several new laptops every week, key drives are useful for storing and transferring all the install files for software apps that should be on a new laptop, but aren't (such as Firefox, AVG Free, and Open Office).
LaCie claims the drive offers transfer speeds of up to 30 MBps in read mode and up to 10MBps in write mode. Our tests, using 6.68GB files, found this to be close to real-world performance. Writing the file took 12 minutes and 32 seconds, for a transfer rate of 9.3MBps; and reading the same file took 4 minutes and 29 seconds, for a transfer rate of 26.1MBps. That's typical for USB flash drives, although some models can offer nearly twice the write speed.