If you are not living in Japan you probably will not hear or read Japanese everyday. Therefore it is likely you will easily forget many Japanese characters (kanji) after a while.
The Japanese basics are always present in my head, but what is happening with more complicated and not often used words? I have to look them up and that is somehow annoying. But nevertheless, I think apart from reading Japanese books and using bilingual paper dictionaries the following sites are very helpful and professional for the purpose of learning, remembering and looking up kanjis.
Asahi-net provides the vocabulary of the JLPT (Japanese Language Proficiency Test) for several devices and languages. On-yomi, kun-yomi and meaning drills are available.
Jim Breen’ Japanese Page is for all people who are interested in Japanese language from the beginner to professional. It is very simplistic, but the most important site I know so far.
I made manythings.org into my start page. It is very simple and easy to use. I get 36 kanji a day to memorize and look them up, if I do not know the reading or meaning. If I have some free time I play some Japanese quiz. Memorizing Japanese kanji with this flashcards is fun and easy. The vocabulary is useful and professional as well. There are words from Japanese newspapers, randomly chosen Japanese words, Japanese Language Proficiency test vocabulary lists and a lot more ready to use.
Extremely helpful is the following article about how-to-guess-a-kanjis-reading-you-dont-know at tofugu.com.
Recently I stumbled upon an article at Gaijinpot, I want to share with you: Nihongo On-the-Go: Japanese Language App Review.
Do you regard it as useful to read bilingual articles as in the Japan Times? I am not sure about that, although it is kind of fun as in this case.
Have you tried one of these methods? How do you practise Japanese and what is your way to remember all the kanjis?