Calling the Top
Some time mid-2013 I was reading through rpietila's posts on the bitcointalk.org forums and came across the theory that you could "call the top" of a bubble simply by selling if the price doubles in 7 days.
Unfortunately, he's got 4.7k-odd posts now, so the exact post has eluded me so far.
While the old trope "past performance doesn't indicate future results" always applies, there's no harm in being prepared to take advantage of an identified pattern should ☞