The Sonic Boom Analogue alarm clock works with vibration, sound and a flashing light. The small vibrating pad attaches easily to the clock and you just put it under your pillow. It vibrates enough so that you wake up - there's very little chance of sleeping through it. The pad is attached by a cord so make sure you do not become entangled in it. The alarm can be set to a really high 'sonic boom' level, while a blue back light flashes when the alarm rings. If you are a heavy sleeper or hard of hearing, this alarm clock should help you wake.