Sure, you can use practically any box in your house to prop your laptop up at a more eye-friendly angle. This DIY Cheapskate Laptop Stand looks slightly more presentable than the shoebox you're using, though (or the taped-up stack of dental floss containers, in my case).
Is it really cheap? Umm.. it's free, actually, provided you've got some corrugated cardboard lying in the house (even a small sheet will do). There are very little shop skills needed as well, since all you'll have to do is cut out the cardboards according to the dimensions specified on the template and put slits on them. It's really that simple.
The DIY Cheapskate Laptop Stand uses six pieces of cut-up cardboards that you can slap together to create a functional desktop accessory. Sure, cardboard is ugly, but it's been designed to minimize the material from showing (most of the laptop will obscure it from front view). According to the author, it can prop up the laptop an extra 8 inches from the table surface, so you might want to adjust the dimensions when you're cutting if you've got a different height in mind.
If there's any potential problem here, it's the fact that it's cardboard. You know, it's not exactly the sturdiest material in the world. The author says his has held up well through multiple uses, though, but he cautions not to leave the laptop on there unattended (you never know -- your cardboard cutting skills might suck, after all).
You can check out the DIY Cheapskate Laptop Stand over at The Closet Entrepreneur, where they also have the PDF template available for download.