Best Japanese study tools on the internet

To any of you struggling to learn Japanese, I came across the most awesome site the other day. iKnow is designed for both English and Japanese speakers and teaches you loads of new vocab in batches of ten words, so you never feel snowed under. For someone who's struggled with horrible books like Japanese for Busy People, this site is a godsend. I also should mention Jpod 101 while I'm at it, which offers free podcasts which are hugely entertaining and relevant to everyday life in Japan.