I got this purely to use as Ready Boost. My second PC only has 2GB RAM, and with Ready Boost, the cache is then stored on the USB stick instead of the Hard disk drive.
Performance increase was very noticeable for that particular PC. My other PC has 4GB Ram, so something like this won't affect that at all.
If you've got a low amount of physical memory, Ready Boost can help out. However, please note that it is still a better solution to just buy memory upgrades.
The USB stick itself is very compact and durable. The retractable male USB connector comes in great handy when transporting (if you do use for your portable data), and has a rather 'cute' price.