Google Docs の SpreadSheet にアクティブなセルに現在時刻をセットするボタンを追加するスクリプト

gistfile1.txt

function onOpen() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var menuEntries = [
     {name: "now", functionName: "writeNow"}
    ];
  ss.addMenu("Write Date", menuEntries);
}

function writeNow() {
  var currentSheet = SpreadsheetApp.getActiveSheet();
  currentSheet.getActiveCell().setValue(Utilities.formatDate(new Date(), "GMT+9:00", "HH:mm"));
}