Often I can tell you how low a stock will trade on a given day by looking at the open book. How? Huge bids at various levels, all around the same size, perhaps 10 cents from each other... once the first one gets taken out, 95% of the time they ALL get taken out. The fewer offers you see, the better. The stock may shake you out, it may take out one offer, bring you beyond your risk tolerance, and then come back, but bids/offers sitting in the book usually always get done. The reason you see all those bids is because the buyers are aware that there's a seller and that they can get their buy orders filled since there will be sufficient supply. On that day a few weeks ago when BBW gave bad guidance and gapped down ~5 points and traded down another 3, this was the case... it was so incredibly obvious that the stock would go lower, because there were so many bids in the book.
This is why I like refreshers, they're not showing you their hand - if someone is showing you his hand, it's because he's the weak hand, not the strong hand. When you see a stock with strong bullish momentum, and you see some huge offer 30 cents away, realize it's almost a guarantee that stock WILL test that offer. If there's another similar offer even higher, then if the stock gets through the first offer, it will get to the second (unless it gets through the first offer HORRIBLY... with terrible speed, incredibly small prints, etc.). Buy up in front of that offer and be ready to buy more once the offer gets taken out, depending on how it goes. If you don't like the way the offer goes, then you can just get out right in front of it.