No, not that kind of fish, although you could probably bait the end and see what bites. This handy tool is an electrician's fish tape, a simple and useful gadget that could come in very handy aboard a boat.

There's not much to it: just a case, a handle, and a one-eighth-inch ribbon of 16 gauge spring steel. Electricians and network technicians use these to pull (or "fish") cables through conduits and walls where hands won't fit. Think of it as a rope you can push on: shove it into a tight space, wiggle it around until you can grab it at the other end, tie it to the wire or rope you're trying to install, and pull it back.

Apart from the obvious use (re-wiring), this could be useful for many other tasks on a cruising boat: getting luff and leach cords into a sail, replacing broken halyards, or clearing clogged hoses, for example.

A 100 foot version carries a \$20-something price tag at industrial and electrical supply shops, but can occasionally be found on sale for \$10 or so.