"Co ja pacze?" is Polish meme, based on "starring cat" picture. "Co ja pacze" means something like "What am I looking at?" and contains purpously used misspelling in word "Pacze" (because it sounds very familiar to proper form of this word - "Patrzę" what means "Looking") and totally wrong syntax (lack of certain pronouns etc).
"Co ja pacze?" is used when somebody witnesses something extremally strange, funny or hard to understand - similar to WTF?!.
i: something strange appears...
Polish: Co ja pacze?