One of the better off-line dictionaries I have seen in a while. Good features, light, and works to search for word meanings from inside an application. Doesn’t use the registry, so mobile – you could carry the dictionary on a USB drive. Also, gives a whole lot of information about the word and works very nicely for anagrams and potentially, for crosswords. Support staff are fun and nice too.
TheSage from Sequence Publishing is a good tool to have on any desktop especially if you have a way with words. A good way or bad, i.e. And if you do a whole lot more with words and languages check out their other stuff.
For a long time I have been relying on The Free Dictionary, from Farlex – and excellent reference tool that goes beyond the dictionary.