A new mishnah! Taking a vow to protect yourself from thugs who you feel are putting you in danger, and you take a vow to protect yourself. With a machloket between Beit Hillel and Beit Shammai, how far that goes. Plus, the law of the land is the law (assuming that doesn't mean laws made against Judaism). Also, another mishnah! The need to redeem saplings (for example) that have been consecrated - with various parameters. Plus, the vows people take in a time of need - like, the protect the saplings, plus the case of the tallit. Namely, promises made as recompense for getting saved.