One of the many New Years' customs in Japan is the handing out of "Otoshidama" (お年玉) -- something of a New Years' allowance where elders give money to their younger relatives. But this being a custom doesn't mean there aren't ways to make it entertaining. See for yourself.
Part of the custom of Otoshidama is that the money given is handed out in small envelopes. In fact, there are dedicated envelopes that are sold in Japan solely for the purpose of Otoshidama. Much like paper money in other countries, the bills in Japan are decorated with images of famous historic figures. Rather than simply hand out Otoshidama each year and be done with it, some people have found more creative ways to entertain the recipients by cutting the envelopes to show the faces inside, or even making their own gag envelopes.
Japanese news blog Oreteki Game Sokuhou @ Zin (俺的ゲーム速報＠刃) has collected various images from across twitter of the interesting, funny, and, in some cases, creepy ways that people have found to put an interesting spin on an old custom.