time_lapse.rb

# requires "isightcapture" in the cwd (http://www.intergalactic.de/pages/iSight.html)

INTERVAL = 20

@t1 = Time.now - INTERVAL

while true
  @t2 = Time.now
  if @t2 - @t1 >= INTERVAL
    @t1 = @t2
    system "./isightcapture #{@t1.strftime("%Y%m%d%H%M%S")}.jpg &"
    print "\n#{@t1}"
  else
    print "."
  end
  STDOUT.flush
  sleep(1)
end