Most alarm clocks are built for the sole purpose of keeping time, while these five homemade creations were designed for much more. The “Man Inside” clock isn’t what it looks like, as you’ll see after the break.

1. World’s Biggest Alarm Clock

Aside from being the self-proclaimed “world’s biggest alarm clock”, this homemade creation is computer-controlled and designed to throw you out of bed, literally. For those with bad backs, be sure to wear a brace nightly to ensure you don’t end up with a strained muscle or two, should you decide to build one yourself.

2. Corpus Clock

According to its creator, this “clock has been designed by the inventor and horologist Dr John Taylor and makes ingenious use of the grasshopper escapement, moving it from the inside of the clock to the outside and refashioning it as a Chronophage, or time-eater, which literally devours time.”

3. Man Inside

No, there’s nobody inside this homemade clock, but rather an LCD that gives off the illusion of such a thing. That’s right, it boasts “a flatscreen that plays a 24 hour loop of this video by the artist watching his own clock somewhere and painstakingly erasing and re-writing each minute.”

4. Pong Clock

With some clever planning and the right parts, you too, can build a Pong Clock. Many have taken apart old laptops, created a custom enclosure / frame for the display, and downloaded a Pong Clock program that keeps time.

5. NES Clock

If you’re a Nintendo fan, or just a geek in general, there’s nothing cooler than having a clock that’s made from an old NES system. This example by YouTube user “aaronmavrinac” even features gamepad controls and a functional alarm.