Following is a list of helpful Japanese learning resources:

Language Learning Methods

• Nukemarine’s Suggested Guide for Beginners is a curriculum of Anki decks and websites that a self learner can employ in teaching themselves Japanese.  The this site is heavily based on his guide.
• All Japanese All the Time (AJATT) is a popular website by a very energetic language learner katzumoto who started learning Japanese and 18 months later passed an interview at a Japanese Company.  His philosophy, as the website suggests, is doing something in Japanese all the time, including listening to japanese talk shows while he is sleeping.  Beware, katzumoto is a bit verbose, so prepare to read a lot of english on his site, but I think he’s on to something and there is something for everyone even if you only want to do some Japanese some of the time.
• Understand Your Favourite TV Series in 30 Days is a method that attempts to do what it says.  The approach is similar to narrow reading where rather than trying to learn “the whole language”, you focus on learning just what you need to understand one television show.
• Input Hypothesis is a suite of 5 linquistic theories by Dr Steven Krashin that essentially language development is a product of comprehensible input (listening and reading) rather than output(speaking and writing) which he claims does not have any significant effect on a learner’s ability. The optimized core 6k anki deck uses Krashin’s n+1 suggestion that optimal learning is accomplished by adding 1 small bit at a time to already understood structures.
• The Movie Method is a method employed by contestants of the world memory championship to memorize large amounts of information.  A modern implementation of the timeless Memory Palace.
• FluentIn3Months is a website by Irish Polyglot Benny Lewis who has been traveling the world for the past 8 years, learning languages in 3 months.  His philosophy is a bit different.  He arrives in a country after cramming vocabulary for 30 days.  Then he goes around speaking in the local language to anyone who will listen.
• Word or kanji frequency lists are another method some people suggest.  The idea is that the most common 2000 words make up nearly 80% of common speech so prioritizing the most commonly used words would get the learner to the point of comprehension in the shortest amount of time.
• Super Fast Vocabulary Learning Techniques is a thread about learning vocabulary fast.  The title is hyperbolic so don’t expect the holy grail here, but it’s worth a read to get a feel for the variety of methods of attack for most time consuming aspect of language learning.
• The Lexical Approach is a method similar to the sentence method, but it could be phrases or clauses instead of full sentences.

Kanji

• Remembering the Kanji by James Heisig.  The bible for most people interested in learning Kanji. If there’s one thing Japanese learners use more than any other, it is this book.  And with good reason.  Also consider Remembering the Kana by the same author for learning your kana.
• List of Kanji ordered by how often they appear in print.

Vocabulary

• AntConc is a concordance tool useful for generating parallel texts, n-grams, and collocates.

Grammar

• Tae Kim’s Grammar Guide is an excellent free guide to Japanese Grammar.
• Kanji – Link grammar lessons is a youtube playlist of well explained grammar points.

Native Japanese Media

• D-Addicts  get subtitles to Jdramas in Japanese and English as well as other languages.
• Opensubtitles has movie subtitles in a variety of languages including Japanese.
• A list Japanese podcasts rated and sorted by theme and difficulty(thank you for this nuriko!)
• Read Your Grade is a list of public domain books sorted by reading difficulty and kanji count.
• The Great Chocochoco Library – An assortment of free graded readers with glossaries.
• Tom Ray’s collection of Japanese children’s stories with line-by-line breakdowns, translations and glossaries.
• Baka-Tsuki is a fan translation community that hosts translations for light novels in the Wiki format.  A great resource for parallel texts.
• Kitsunekko is a website where you can find subtitles in english and japanese.
• Bilingual Sentence Aligner is a perl script that aligns a text with it’s translation on a sentence by sentence basis.  Useful for reading parallel texts.
• Japanese Graded Readers are a series of books created to practice reading Japanese at your level.  A little expensive, but highly recommended.
• List of Japanese public domain books ranked by difficulty.
• Learn Japanese from Dramas lets you learn colloquial Japanese via parallel transcripts of Jdramas and a little usage explanation.
• Lingocracy is a website where you can read pages from the web while translating and marking unknown words for later study.
• Readlang is a browser extension which translates hovered text and creates flashcards of unknown words.  (web, iOS, android) (Freemium)
• Lingq is a website where you can read in your target language and translate and mark unknown words for further study.
• Furigana Generator and Furiganizer add furigana to pasted text.
• Hiragana Megane adds furigana to any Japanese website.
• GLOSS  is a website that creates lessons using native materials to learn languages.

Dictionaries

• JDIC is a searchable online dictionary.
• jisho.org is another dictionary site.

Anki & SRS

• Anki is a popular flashcard program for desktop, web, and mobile platforms.
• AnkiFox is a Firefox add-on which adds highlighted words to anki from any webpage.
• fuzzy-anki is a tool that exports a csv file of learning information from your anki decks for analysis in excel or other data analysis software.
• Theoretical aspects of SRS from the supermemo website.

Other

• Lang-8 is a language learning platform where native speakers correct what you write.
• tanos.co.uk/jlpt/ has a lot of useful information about JLPT tests like kanji and vocabulary lists for each level, practice tests and a level checker to test your knowledge level.
• Tatoeba is a large, searchable database of example sentences translated into several languages.
• How to Improve Your Foreign Language Immediately by Boris Shekhtman.    A short book with a lot of practical advice about how to put what you know to use.  Exactly the kind of book I like.