I'm in the mood for dansyl: A chemically controlled fluorescent logic gate was formed by grafting a dansyl unit onto silicon nanowires (SiNWs; see picture). The logic gate was operated by utilizing pH changes, Hg(II), and Cl(-) or Br(-) ions as inputs and the fluorescence of the modified SiNWs as output. The modified SiNWs could perform as a three-input logic gate that combines the YES and INH operations.