Household GOOP [http://www.biosafe-inc.com/ag_adhesives.htm].

All of my old second and third-tier hiking, walking, and cycling shoes are held together with this stuff. I even slop it on the lugs when they start to wear down.

Get it at Lowes/HomeDepot...keep it handy and in the same place you put your duct tape.

When the Laws of Physic are repealed, we'll hold the universe together with GOOP and duct tape.