Welcome to FT.

Over the years I've had lost luggage straps and all sorts of tags. One thing that's easy and relatively distinctive is the scuba-suit-like handle grips. These go around the luggage handles and secure pretty well with Velcro.

If you want unique (meaning looks different and is different than almost all other travelers), I'd suggest you go to a sports store and get the wrap used for tennis racquet handles. Wrap your luggage handle with this stuff. Comes in many styles and doesn't normally come off.

If you want classy and distinctive, you can have your luggage custom embroidered. Kind of like a bag tattoo.

If you want cheap and distinctive, you can get a can of day-glow green and/or orange spray paint and "tag" your bag.