I adored these books when I was a kid, and a few of us friends re-invented them in college in the 1990's as email chains. You'd write a few introductory paragraphs and a choice, and then email it to a few friends. You'd then end up writing multiple paths as you went, depending upon what your friends chose. The first one I wrote started as just a scruffy little dog who escaped his backyard. He ended up going on all kinds of wild alternate adventures, and did, unfortunately, end up dying quite a few times.