Date: approximately 12-28-2011: or one day before or after at most. Time: late night: 10:30pm--1:30 am. Reporting it this late because it occurred to me that it may help someone else. I first thought it maybe was a nova, and looked for it in the news--there were no novas reported.
I was sitting in a chair in my backyard looking up at the sky for over half an hour(just thinking about the year behind me) before I settled on looking at what I took to be a star. There is a power line going to my house just under the object(approximately one moons diameter), making a good reference point.
I was staring right at the "star", lost in thought, for at least 10 minutes when it quickly got 3-4 times bigger, and at the same time brighter, then just blinked out--gone. It had been stationary, quiet,a steady white light,and, I would guess, miles away--towards downtown Los Angeles from me, but who really knows how far.
I know the flight paths around here, and they are not in the same area, and they are ruled out anyway because this was a stationary light for over 10 minutes, on a clear night. That is all. I had just slight puzzlement and some excitement to think I may have seen a star go supernova. I will add that after it blinked out, I remained sitting out back, so total time was probably an hour to an hour and a half.