Perhaps this counts.
Aged maybe 10, if not a year or two younger.

Along with 3 friends, I spent the morning digging a rather large hole in the middle of a public footpath going through some woods near my house. It was probably only a foot deep in the end, and maybe 3' x 3' wide/long.

Having accomplished this without being caught, we placed fine branches across it in a criss cross pattern, covered those with leaves and left it looking much the same as the rest of the footpath.

Unfortunately, and anticlimactically, we didn't hang around to see the results. I'm farily sure whoever got caught by it would have ended up on their knees in the hole, at best.
(username failed moderation, Mon 20 Feb 2012, 15:14, 4 replies)

You see?...

This totally fits the requirements of the QotW...unlike many of the others that don't seem to 'get it'

Therefore - I click thee
( Pooflake braces for an onslaught..., Mon 20 Feb 2012, 15:42, closed)

I think for it to be really evil
we'd have needed to put sharpened spikes in the hole.

To be frank, at that age I was so shockingly irresponsible that had the idea occured to me, I wouldn't have thought twice about it.
(username failed moderation, Mon 20 Feb 2012, 16:33, closed)

click
We used to line a hole with a fertiliser bag and nick pots of paint from my dad's shed to fill it up with. A sprinkling of mud and leaves on top guaranteed a trail of magnolia footprints the next day.
(oneinthepink is at your cervix m'lady, Mon 20 Feb 2012, 18:25, closed)

Phew.
So it wasn't just me. I will have a companion in the eternal fire.

So that's nice.
(username failed moderation, Tue 21 Feb 2012, 8:25, closed)