[vidarh]

If your biggest weakness is a major problem, then hopefully it is also something you're urgently addressing. If you're unfortunate and have to apply for jobs while you're still working on that aspect of yourself, then you may need to find a way to sell it, but really for most people this shouldn't be something you need to agonize over for very long.

Of course everyone who asks this question is looking for how you reply, and don't necessarily believe you'll tell them the absolute truth.