Google Apps Script snippet to run time based triggers during specified periods

gistfile1.js

function scheduledCollection(){
  var schedule = [];
  // dates/times in mm/dd/yyyy hh:mm - timezone matches settings in File > Project properties 
  schedule.push({start:"08/29/2012 15:00", end:"08/29/2012 16:00"});
  schedule.push({start:"08/29/2012 20:00", end:"08/29/2012 22:00"});
  checkCollect(schedule);
}

function checkCollect(schedule){
  var now = new Date();
  for (i in schedule){
    var start = new Date(schedule[i].start);
    var end = new Date(schedule[i].end);
    if (now > start && now < end){
      // insert function you want to run here
    }
  }
}