痛車 From the kanji for Ita/pain and Sha/car. Sometimes referred to as a "pain car".
These are cars that are covered in illustrations from anime or games. It's a blatant way for otaku to represent their interests.
ExamplesHikounin Sentai AkibaRanger is an itasha called Machine Itasshaa. It's decorated with an illustration from the anime Z-Cune Aoi.
痛ちゃり Ita-chari or "Pain bike".
In Oreimo, Kyousuke borrowed an itachari to get home from an Akiba midnight sale. The bike was decorated with the girl from the Onipan game series that he was picking up at the sale.