Television directors used to communicate to talk show hosts with lighted signs saying that their time was almost up. Dave Chappelle was inspired by this tradition to create a sketch about a man with his own personal "wrap it up" box.
I'd love to have one of them. I'd wear it around my neck all day and turn it on when needed. Now that's actually possible because Spikenzie Labs built a working model. At the link, you can view detailed instructions and process photos on how to make your own.
Link via Make
(for those that never looked at mode 2)