With SakuraDict you can search the dictionary for kanji and words. You can input text in English or Japanese (kana, kanji and romaji accepted). It also understands skip codes!
For example to look for kanji 試, you can:
Sakura Dict also features a powerful advanced search that allows you to use a lot of criteria.
This section feature links to reading materials on the Web. For this Beta, the list is limited to Wikipedia articles. Links can be filtered by length and by difficulty levels (based on JLPT).
For every material, the link sends you to the article itself. Click also to the difficulty rankings to get a list of more common characters and words in the page, so you can study them while you are reading.
This is the only section in Sakura Dict that requires you register and log in. You can create lists of words and kanji. You can then retrieve these lists when you need them and, share them and soon you will be able to export them to your favorite SRS software.
To add an element to a list look for + buttons in the search results or in the kanji or word pages when you are logged in.