Sold mine @ 35.33 a couple months back. Bought it in 2005 for 29.68 and watched the ups and downs for almost 2 years. Will buy back in around 29 again, but won't miss those chances to sell and make money again. CHK is like shooting skeet. Once you get a bead on it, you can hit pretty consistently.
Any stock can be profitable if you study it long enough. Pick out 10 stocks and study them for long enough and you can steadily increase your money (and conversely, not lose any).
As far as the market crashing, unless you own poor companies in off sectors, you don't lose your cash in the long run if you hold. And no depression is going to be allowed to last more than a few years. The big boys can't profit if we stay broke. If I remember correctly, GM, GE, Ford etc were around before and 'after' the great depression.
If your dollar is losing 4% per year, you only need 7.66% to double your money in 20 years. And at 20% your dollar would be worth %17.50. And your stock certificates will be safer than cash if the banks go down. Because cash is not King. Kings don't depreciate over time. If you hold cash only, your dollar of today will only be worth .46 in 20 years with 4% inflation and we know some things are going to inflate more than that. At that rate, Milk will be about $9 per gallon, bread $3 a loaf, gas $6 per gallon. I don't even want to think about homes and healthcare (shudder).
I know Lobo likes gold, but it will only be worth what the government says they'll pay you when they come to get it from you (ie 1933). And I would not give you a fish for it (I live on the coast). The big boys keep their gold offshore to avoid that scenario.