According to Yahoo! News:
As just about anyone who’s ever worked in an office can attest, one of life’s most festering annoyances are people who don’t return pens that they borrow. Now it appears as though Czech Republic President Vaclav Klaus may be one of those people, and the citizens of the nation he rules over are none too pleased about it.
…You can watch video of the incident, complete with graphics and a humorous soundtrack, below: