I have done a few of these myself through the years.
One time I was doing a major remodel on an old house and went to hang the fluorescent strip lights on the kitchen ceiling. The old ceiling was lath and plaster so I used a couple of long wood screws to mount them with. I thought it worked pretty well until I had to move one fixture that didn't quite line up. I had sunk the screw right into the upstairs bathtub drain trap. The water went all over the new oak kitchen cabinets with the GC standing right in front of me.
Another time I was installing an outlet in a nursing home for a TV. This was an old building and the walls this time were lath and plaster. I laid out the opening for the box and cut the hole in the wall-right in front of the drain line for the bathroom sink. I thought well that isn't too bad, just move the hole and blank up the mistake. Second try was worse, I found the drain stack for the second floor hiding in the wall. I still needed to get the outlet in, so I moved the box again for try number three. This time I found a cold water line hiding there. Right about then my helper left the room because he was loosing it while I was left wondering if I had enough blank plates in the truck to cover all the damage. I got the box in with the next hole I cut. The maintenance guy was pretty cool about it all. He took part of the blame because he told me that he wanted the outlet "right there".
I try to check on both sides of a wall now before just cutting in to it.
[This message has been edited by fla sparkey (edited 10-03-2002).]
