Google recently put a thing called Google correlate up in their labs.
You enter a query and it finds other queries whose volumes correlate with your query in time. If your query has spikes at different times since 2003, then in practical terms, Google correlate finds other queries that spiked at the same time.
The fun part is that you can shift your query in time. If, say, you shift your query by -37 weeks (a pleasant prime number not very near any natural time cycle), you can find other queries that ebb, flow and spike 37 weeks after yours.
So, try “osama bin laden” shifted -37 weeks.
The results: Three “aim 5” queries and “best dvd rentals”.
Coincidence? You decide.