I've always used vocabulary games in my classes. They are fun for me, and great for the students. And now, with the help of the computer, there is no end to the wonderful things that may be done while playing around.
When engaged in a game, the students don't even realize the number of words they are coming in contact with, they don't mind the challenges [it's all part of the game], and compete to outdo each other [or themselves].
The lexicon in games is out of context, so they are a great way to activate dormant vocabulary, the items that only go on in the head when reached with the right association. In the games the word is only linked to a picture or to a set of words related by topic, therefore demanding a more skilled juggling of words.