CC AutoDropper

local inputSide = "back"
local outputSide = "left"

local function output(line,str)
    term.setCursorPos(1,line)
    term.clearLine()
    term.write(str)
end

local function hasItem()
  return rs.getInput(inputSide)
end

local _blink = true
local function blink()
  rs.setOutput(outputSide,_blink)
  _blink = not _blink
end

output(string.format(1,"#%d - %s",
    os.getComputerID(),
    os.getComputerLabel))
sleep(1)

while true do
  rs.setOutput(outputSide,false)
  if hasItem() then os.queueEvent("redstone") end
  os.pullEvent("redstone")

  while hasItem() do
    blink()
    output(2, hasItem() and "Has item" or "No item")
    sleep(.1)
  end
  sleep(.2)
end