I'm skeptical about some of these. For example, regarding the Laura Buxton story, I think it's more likely that it's an elaborate practical joke that they went to great lengths to make people think it was real.
Or the lottery winner - it seems more probable that someone had insider information and knew exactly which tickets to purchase.
If all of these were truly random events, I'd say the Laura Buxton story is the most improbable.
The media was all over that one in the UK and investigated it pretty well, as I recall. But a hoax is always a possibility.