Third for meditation practice. On a subtle level, the mind when distracted is attempting to be somewhere else, and training in coming back to exactly where it is now is a good way to work with your habitual behaviors (procrastination).

Meditation changed everything about my life -- similar to the OP I also slid by on smarts and not hard work, but started practicing meditation in college due to general anxiety and went from a B- to A+ student--I didn't even work longer, but just had more focus and mental stability on the task that I was performing at hand, which ultimately allowed me to get more done.

Plus, once you're in the habit of applying some type of discipline that's not about the end result (e.g. I always gave up on projects because I wanted them to be amazing right off the bat) it becomes much, much easier to be willing to put in non-grandiose, day by day drive necessary to accomplish /real/ things. Put another way, when you pay attention to the details, suddenly that overwhelming urge toward "greatness" or "brilliance" fades away, and you can actually get things finished.

Agreed, don't beat yourself up about this. It's a very human problem, and even recognition of your current circumstances is far and away above what many people ever accomplish.

Thank you, I should have mentioned that Mindfullness is an evidence based therapy for a bunch of things (depression, anxiety) and has also been shown to improve concentration (especially in heavy multitaskers - I believe the study was personal assistants.)