For me this is common. Not so much in the "saved the company" sense, but rather in the "oh, I know how to solve that" sense.
And only occasionally for big things. More often for little things. Bug fixing. Feature design and so on.
I seems when I stop looking at the problem so hard, the solution works itself out subconsciously, and is waiting for me the next time I think in that direction. Usually in the shower :)
Of course this is just the beginning of the actual solution. The work is in taking the idea and then turning it into something useful. Ideas by themselves are valueless.