Generally nothing fazes me when I fly, but being struck by lightning came close. I was sitting near the window when I simultaneously saw a flash of light out the window and heard an explosion. My immediate reaction was to try to determine if the plane was still cruising normally. Fortunately, the pilot immediately came on the PA to announce that "you now know what it feels like when an airplane is hit by lightning." He assured us that it is not at all dangerous and that the plane was operating normally.