A Japanese person who's ability to write in kanji has suffered because of his or her reliance on computer input systems. * Waapuro means "word processor" (it's just a bastardization of the English word) and "baka" means "idiot." Thus "word processor idiot." This is one of the few words that is almost completely culturally incompatible for translating into other languages. It also may be the most useless words for a gaijin to know.
* Because kanji has over 3000 commonly used characters, they can't all be put on a keyboard. Instead, computers often use a system where words are entered in roomaji (pronounced roh mah ji, the Japanese writing system that uses western letters) or kana (either of the two phonetic Japanese character sets) and translated into kanji afterwards (i.e. via a pulldown menu).
Ano hito wa waapurobaka desu yo. Tabun "neko" o kaku koto ga dekimasen.
That guy is such a word processor idiot. He probably can't write "cat".