Every once in awhile I come across the classic "buy me" formation. Actually this happens a lot more often than you might think. A down sloping day followed by a gap down that doesn't stay down and forms a long tailed hammer and then away it goes.
When you see one of these you can be fairly certain (80% or so) that it will go up. I like waiting until the third candle (and in this instance actually waited until the 5th) for a confirmation. I bought this off the "retreat to 8" set-up that I like so much which actually gave the trade a much higher probability of success.