This seems to happen to me often.
I'll hear or read some obscure bit of information somewhere in the news, a forum, etc... Within the next day or so I hear about it again, and then sometimes a third or fourth time.
A few days ago I was watching Modern Marvels and the program was on hot peppers. They talked about the hottest pepper in the world, the Bhut Jolokia
pepper from India.
The next day I was reading the news and saw a news link about how the Indian Army developed a grenade
that showers people with hot pepper dust. Without even opening the link I knew they were talking about the same pepper.
This happens often. I think it's strange, but I learn a lot that way.