There’s a meme going around the book blogging community that goes roughly like this: you open a book to a certain page, find a line a certain number of sentences into that page, and then quote the next several sentences. At face value this sounds kind of uninteresting, but in practice it results in some absolutely fascinating out of context quotes. When you reach deep into a story and take several lines on their own like that, they can often spur the imagination in interesting ways.
Today, pick up a book and open to a random page, preferably one at least a little ways in and preferably among pages you haven’t read yet (even better, from a book you haven’t read yet). Locate the third sentence on the page, and then copy down the following three lines.
Using these three lines as the beginning or end of your piece (or inserting them somewhere in the middle), free-write for five to fifteen minutes.