I did a lot of online courses and self-study things like that while I was in college. It's all fantastically interesting, but it can be very time consuming if you accidentally let yourself get going on too many classes at once :) I managed to learn enough about web design and javascript in 3 months (and 4 years of previous, non-web programming experience) to land myself a job doing it, so I'd say it can all work pretty well if you really work at it.
I've dropped most of that now because I haven't found many that focus on my current area of study (music education), so I'm stuck with more traditional text-based sources at the moment.