We've reviewed drive docks before – devices that let you mount hard disks on your Mac without wrestling them inside an enclosure first – but none so compact and handy as this one.
It has three ports for three different types of drive: there's a slot for a CompactFlash card so you can easily import pictures from a digital camera that uses it. There's no support for SD or any other memory format, though, so this is only likely to be of use to high-end camera owners.
The important bit, however, is that on either side of the HI-2503 there's a slot for the two different types of hard disk interfaces, IDE (sometimes called ATA or PATA) and SATA.
They're designed only for 2.5-inch laptop drives so you won't be able to use this if you need to access information on a 3.5-inch desktop drive, but the support for IDE and SATA makes is a very flexible system for the smaller-format disks.
It's simplicity itself to use: you simply slot the bare drive you want to access into the appropriate side, connect the dock to your Mac over USB, and you're ready to go.
You can do everything you would if the drive was fitted inside an external case – copy files to and from it, format it, erase stuff – so it's a great help if you regularly work with small notebook drives. It would be a great way, say, to clone your MacBook's hard disk to a new, larger disk before you fit it yourself, something that's really easy to do with the MacBook line.
It happily bus-powered the drives we tried it with – no messy extra cables needed here – though while it would mount a hard disk and a CF card simultaneously, it understandably balked at trying to power two notebook drives at the same time.
It's certainly not a product with mass-market appeal, but it gets our thumbs up because it does its job with the minimum of fuss and at a wallet-friendly price.