Did you know that Facebook is claiming a trademark over the word “book”? It has even revised its user agreement to add “book” to the list of trademarks users agree, by accessing the site, not to use without Facebook’s written permission.
This springs from a series of trademark lawsuits or complaints that Facebook has been launching against various other sites that name themselves “(something)book”, such as Teachbook, Lamebook, and Placebook. (Because, clearly, nothing else was ever called "(something)book” before Facebook.)
The funny thing is, “book” isn’t actually even trademarked to Facebook in the US. (It’s pending in Europe, but is opposed due to likelihood of confusion so may not go through.) Even if it was, of course, the trademark would only apply in a social media context—it wouldn’t mean that Facebook could sue businesses for calling themselves “bookstores”, for example. But it sure does sound silly, doesn’t it?