The company makes a line of retractable barriers, sort of like the ones you see in banks and airports, that stick to the sides of your cubicle entryway. When you need some uninterrupted work time, you simply pull the CubeGuard across and latch it in place.
It's sort of like "Do Not Cross" police tape for the office.
You can customize your messages or select from standard versions. Want to display a bunch of different messages? Just purchase an assortment of message cartridges -- e.g., "I'm out of the office," "I'm out to lunch," "Do not disturb," and so on.
At $20 for the whole enchilada, and $15 for each message cartridge, it's reasonably affordable and a lot more slick than taping handwritten notes to your cubicle wall. On the other hand, it seems a bit cutesy for my taste, and I think the novelty might wear off quickly.
Let me know what you think. And have a great weekend!