Rather than spend hours watching Nyan Cat online, dress like it this Halloween. First, dress like a gray cat; gray leggings, long-sleeve shirt, and cat mask. Create the Pop Tart by painting two pieces of cardboard the same, and affix strips of rainbow-colored fabric to the end of the board. Use a thick fabric to join each side of the Pop-Tart together and wear over yourself. For the most enthusiastic of Nyan Cat fans, check out this more extensive DIY costume tutorial.
Source: Flickr User Rob Boudon