I have been using this Malayalam Dictionary (http://www.mashithantu.com) for quite sometime and I found it to be a very helpful tool for us who want to express our thoughts in our mother tongue and get mastery over the language.
Mashithantu has a huge database of 60,000 Malayalam words and 27,000 English words. The features like ‘matching section’ make it even more powerful by suggesting the right words intuitively. It’s a like of mini-spell checker. I am sure you will like it.
Recently they have come up with an interesting Crossword competition, that too in Malayalam. An easy and hassle free registration will take you to the exciting world of Crosswords at http://crossword.mashithantu.com/ .