My Submission

--This is a little screensaver.
--Made by H4X0RZ (I guess some people on the forums reqeusted this...)
--To leave it, enter the password and press enter (if no password is entered just press enter)

--checking if advanced computer
if term.isColour and term.isColour() then

else
  error("Please use an advanced computer",0)
end

--Varialbes
local input = ""
local password = ... or ""
local oldPull = os.pullEvent
os.pullEvent = os.pullEventRaw
local running = true
local BGc = colors.lightGray --Background color
local Lc = colors.green --Line color
local l = {} --lines
local screenWidth,screenHeight = term.getSize()
local speed = .4

--Initialization
for i = 1, screenWidth do
  if i % 2 == 1 then
    l[i] = screenHeight
  end
end

--functions
local function reading()
  while running do
    local enter = false
    while not enter do
      local sEvent, p1 = os.pullEvent()
      if sEvent == "key" then
        if p1 == keys.enter then
          enter = true
        elseif p1 == keys.backspace then
          input = input:sub(1, #input - 1)
        end
      elseif sEvent == "char" then
        input = input .. p1
      end
    end
    if input == password then
      running = false
    end
    input = ""
  end
end

local function update()
  while running do
    for k,v in pairs(l) do
      if math.random(1,2) == 1 then
        if l[k] > 1 then
          l[k] = l[k] - 1
        end
      else
        if l[k] < screenHeight then
          l[k] = l[k] + 1
        end
      end
    end
  sleep(speed)
  end
end


local function display()
  while running do
    term.setBackgroundColor(BGc)
    term.clear()
    term.setBackgroundColor(Lc)
    for k,v in pairs(l) do
      paintutils.drawLine(k,screenHeight,k,v,Lc)
    end
  sleep(speed)
  end
end

--main loop
parallel.waitForAny(reading, update, display)

--The end
os.pullEvent = oldPull
term.setBackgroundColor(colors.black)
term.clear()
term.setCursorPos(1,1)
term.setTextColor(colors.yellow)
term.write(os.version())
term.setTextColor(colors.white)
term.setCursorPos(1,3)