I just love all these game things were making! So i finally thought of one i wanted to post, me and my family just made it up on a vacation once, and it's really fun and challenging :D.
So basically, you just say some sentance, quote, movie or TV or book title or any other thing you can think of, and make all the words you can, an opposite word. It's hard to explain, but I'll give ya an example :)
So you would comment something like:
The slow green xof slips under the energetic cat.
People would respond guessing at what it is. For that ^^^ someone may guess:
The quick brown fox jumps over the lazy dog.
and then you'd respond and tell them they got (of course ;) ) and if you can't think of an opsitite to a word you could maybe spell it backwards ('xof' for 'fox') or leave it the way it is (like 'the').
So, comment, guess, enjoy!