Hmm, I have to list 3 things and they all involve
cars and my complete lack of depth perception and attention span; and I'm actually pretty lucky to be alive when you think about it

I think the 3rd and final one (I got my license taken away, I haven't cared to get try and get it back yet.) is the stupidest, but they're all pretty dumb.
Accident #1:
My horrible eye sight amongst other things, decided to create an imaginary third and fourth lane between me and the other lane people were driving on. I attempt to drive into the imaginary third lane, drive into another car. (Thankfully not at a very high speed :S)
Accident #2:
Attempting to enter a lane from the intersection, when I finally think there's time for me to turn without a car coming by, I hit the gas pedal a little too hard, turn a little too hard, spin out and end up smacking into a lamp post.
Accident #3: Drowsy amongst other things. I was NOT paying attention, and sort of having a day dream that I was back in my hometown in the UK, completely forget I'm in the US and drive into the oncoming lane. Thankfully, there weren't many cars out and it wasn't a very busy street, but there was still someone out there who honked which startled me, I swerved, ended up hitting a tree.
As I said they took my licscence away after #3, and I'm not going to bother getting it back because I'll probably continue to suck at driving, and I don't really feel its worth risking my life or anyonelse's lives just because I can't drive worth crap. In fact another reason #3 was really dumb is not only that time was I endangering my life and anyone else who was on the road, I was endangering my wife Chie's life too because she happened to be my passenger at the time.
