It helped me come out of alcohol and drug addiction (not after a single 10-day course, mind you). It's helped me a great deal with long-standing anger issues. I find myself much more lucid and generally more effective; my decision-making capability is a lot sharper than it was 5 years ago.

Some effects which coincide with my Vipassana practice that I would say are hard to attribute to it (but I'd be tempted) include: calling my parents more often, giving people my attention more meaningfully, an improved diet, and better results from exercise.