Naphthalene (not para-dichlorobenzene) mothballs can be used to get a fire going in a survival situation if you don't have adequate tinder available. It's not for routine use since the vapor and especially the sooty black smoke are harmful to the environment and to you. Naphthalene mothballs do not burn especially well (para-dichlorobenzene not at all) so you'll need some tinder to warm the mothball and release its flammable vapor.
—David Foss