My submissive mistress is always commenting that I must walk through a Lowe's store (big box, U.S. hardware store) with an erection.
I've made a small flogger using an old belt, leather shears to cut the tines, a small piece of dowel for the inner handle and electrical tape to cover the "grip".
Metal "links", chain lengths, rope lengths, "snap" locks, even an expandable shower rod for a portable "hang bar" in a motel are all good examples of the imagination's ability to work on the fly.
Alligator clips dipped in the liquid "rubber" make excellent clamps. (Her marriage deems it unwise to leave scars or permanent marks...)
Hand held vise clamps for breasts, buttocks or simply clamped to a door frame for tied suspension... ah, the list could go on all nite.

best,
monsignor