Another electrical fire hazard...

The previous owners of the house were good at some things... carpentry for one. The owner was a builder / carpenter and he was doing stuff on the house for themselves so he did an awesome job at it.Electrical, on the other hand, does not seem to be his strong suit.First there was the dish washer issue that I ran into a few months back. That one could very well have caused some serious issues -- like burning down the house for instance.Today I was replacing a standard wall switch in the bedroom with one that has a dimmer and I ran into another issue: an overcrowded wire nut.So the actual replacement was pretty much run of the mill. You take out the old switch and you add in the new one. The new switch, being a dimmer, is physically bigger and comes with a bonus ground lead which also adds to the overall stuff inside the box.I installed things, turned on the breaker and started to do the final tightening of the switches into the box when I saw a bit of a flash. At the same time the lights in the room -- not just the ones I was futzing with the switch -- went off. That's not a good thing. So, the breaker was turned off again (no, it didn't trip the breaker) and I uninstalled the switches again.Looking closer it was clear what the problem was: there was six 14-gauge wires going into one wire nut that's specced for only five. It doesn't seem like a big problem, but since it wasn't fitting correctly the wire nut wasn't really attached to any of them. It was an accident that it worked the first time around.Oh... and the arcing...  :-OI replaced the one nut with two and a little pig-tail to keep things in spec.That, of course, fixed things.sigh...Most people are afraid of electrical work. They ought to be if they can't do it right.I'm just wondering what other janky things are lying in wait...