Taught Java for several years at university. Didn't like it, and didn't really pay attention. In some strange moment I decided I would base my final year project on a PHP application. None of the tutors knew PHP, and I wasn't ever taught it during my course. Bonus. So I didn't have much choice but to buckle down and learn it in the best way there is, by practical use
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. 10 weeks of coffee-fueled late nights (not that that was any different to previously). Now I get payed to do it. Bonus.
PHP and MySQL Web Development by Luke Welling, Laura Thomson was a good read and a recommended practical introduction.