I mean... Seriously. Its a wire. You could use long nail driven into the ground with a wire tired to it and to your skin.
Anti-Static wrist straps are a sham.
TBH, I have fried a few components back when I used to do PCB repair. However most motherboards are coated before they are sent out these days so usually your not touching anything bad (unless you intentionally touch an IC of some sort).
Anti-Static wrist straps aren't really a sham, or rather to buy one (or more) would be a sham. The object isn't to ground yourself to ground (of your home/office), but to the ground of the device (like the computer case). Basically you want something OTHER than a circuit/IC between you and the Ground pole (in this case, the ground of the psu which isn't always the same as the ground wire of your home or office).
Most can get away with-out the use of a wrist strap (just continually touch the case metal with your fingers, or lean up against it with your bare arm from time to time to ensure you carry no charges that differ from the ground terminal of the psu).