Fabulous Magic 8 Ball Prank

Hackaday forum user [arfink] has shown us a brilliant practical joke he built. This is a magic 8 ball that will blind you with a flash when you flip it over. Have you ever been in a room with one of these and not flipped it over? Neither have we. Using a basic flash circuit ripped from a disposable camera in conjunction with a mercury switch, this project took him about 2 hours to make. Admittedly, most of that time was just trying to split the 8 ball in half without completely destroying it.  The circuit is pretty simple. Just figure out what 2 wires need to be crossed to trigger the flash and install your tilt switch there. He added a power cut off so you could disable it as well.

UPDATE: video added after the break!


37 thoughts on “Fabulous Magic 8 Ball Prank

  1. Pretty nice simple hack.

    The only improvement I can see is changing the flash to a high powered LED. The big ones can put out a blinding amount of light, but don’t require a high voltage capacitor to stay charged like I think most flash circuits do.

    That might reduce the idle power consumption.

    Also, to disassemble it, just break out the clear window. Since, by the time the user sees that part of the 8 ball, it doesn’t matter what it looks like, you don’t have to worry as much about what you replace that section with. As long as its flat so that when they pick it up they don’t feel anything weird.

  2. @Zool, they will definetely look at it, if it doesn’t feel right when shaking, if the flash doesn’t trigger first. Hell, even if it triggers, they will still look at it to try to figure out wtf just happened.

  3. Nice hack on tech merits and unexpected “WtF?” aspect. Getting too elaborate and having a hack never get built is a fail that’s had many projects die stillborn. Arfink scores points for e job done more than just “Good Enough” that actually got built.

    Perhaps an expansion of the concept might be tucking a cam into the ball for capturing those Wtf? expressions.

  4. Brilliant!

    to slow the flash a little a resistor and capacitor at the mercury switch? i meen how longs it take u to grab one off a table to get a gd view of what its gonna say?

  5. @PocketBrain

    There is no more injury happening here than any that might occur from a close up picture taken at night…although if someone were epileptic this could cause them to go into a seizure since the flash is obviously a surprise.

    I fairly certain that it takes multiple flashes of light to trigger an epileptic’s seizure response. (I’m a RN at a state mental hospital so I know a few things about epileptics).

    Side-note: My great aunt was epileptic and she took group pictures with us all the time involving multiple flashes, so in totality I really don’t see how this could harm anyone.

  6. I’m with Oren for version 2. The camera would be an awesome add. But, if I were going to go to that much work, I would replace the flash and mercury switch with an accelerometer and high power LED. That way, it won’t fire off before faceing up.
    Then I’d add a weight so that feels right when picked up, and then…

    Yes, long before this point it would never get finished, just like Oren said…

  7. Thanks for the feedback. Yeah, this was a cheap no-brains hack. Also, as a side note, the mercury tube does make a sloshing noise which is somewhat like what the blue goo tube does. It’s fairly convincing.

  8. go with my version
    buy http://cgi.ebay.com/110632493890 for $75
    add 2 d cell batteries and a driver circuit, make sure to include a small delay after mercury switch is tripped, so the person can see the little note “goodbye light, hello world of darkness”


  9. Sorry to be a party pooper, but pretty irresponsible IMHO. Even putting epilepsy to one side (which can still be triggered by a very bright flash – just because your aunt/gran/uncle/etc – delete as appropriate – doesn’t suffer from a single flash, doesn’t mean no-one else does), you can easily give someone a migraine with this. If you’ve not had one before, I suggest you look it up. it would have been much funnier to just build a camera into the bottom with a small white LED which came on enough to illuminate the subject and have the obscene answer to be captured on digital memory inside.

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