If you've ever tried to use a typical computer or tablet in direct sunlight, you know that it's pretty much impossible to read the screen.
Indeed, it's practically impossible to use a normal laptop, smartphone, or tablet with a normal glossy LCD in direct sunlight. Yes, matte finish screens are somewhat better, but still difficult to read. Users can opt for something like a E-Ink display, but the screens don't support video - limiting the mobile experience in other ways.
Recently, a company known as Sol Computers introduced a 10-inch USB monitor based on a Pixel Qi display. The monitor draws its power and connectivity from a single USB port, making it pretty convenient to use on the go. However, you really want to be sure you need a sunlight-readable display before splashing out some cash, because this device sure isn't cheap.
Indeed, the Sol display carries an $800 price tag. The best part about the unit? When you turn on the backlight, it looks like a standard full-color display, allowing it to be used normally in your home or office. When you turn off that backlight, you can see images on the screen using the bright ambient light around you. However, with the backlight off it does look more like a black-and-white screen than a typical color display.
Liliputing speculates that the price is so high is because this monitor is most appropriate for industrial, military, or aviation use. Personally, I think the screens will probably eventually find their way into normal laptops, if the price comes down. Plus, the screens are produced in relatively small quantities, which also adds to the price.
However, one thing is for certain. Quite a number of users who might be interested in a screen that can be read in direct sunlight aren't going to want to tote around an external USB monitor.