I'm working on more games for insomniacs--"The Apophatic Bookstore," "Symphony Orchestra," "Chicken Farm."

"Cento" is one I've used myself. You simply keep a steady stream of famous lines of poetry, or lines you've memorized in the past, going for as long as you can in your mind. You can use single lines, fragments, or whole poems, and break off a fragment whenever you wish and go on to something else.

Unlike "The Complete Sentence Game" Cento is not theoretically infinite. At a certain point you will run out of poetry to recite to yourself in your head. You will never run out of sentences.

"Sentence Fragment" resembles The Complete Sentence Game except you can freely intersperse fragments of sentences. Like this one. Or this one. Make sure you come to a full stop, marking the end of the fragment with a mental period.