What is something witty to say when people (usually kids) point at you and say "FARANG! FARANG!", while looking at you like you're an alien with three heads?

I usually say "manang dek noy". Is there something more appropriate? The other day a young girl, probably 6 years old, came up to me and just stared at me saying "FARANG" over and over. What is the best way to respond?