the 'relevance of grades' argument never seems to die here. like any other measure of ability, the use of GPA has its limitations. the reason the debate continues, i suspect, is that a lot of people here got bad grades.
So from my perspective, GPA is about 95% useless in real life.
In any case, I hesitate to offer my own examples: I don't have a sufficiently large sample size, as I don't hang out with people who had low GPAs.