They are easy to make from cheap carbon arrows courtesy of your friendly neighborhood cheapo sporting goods store. You can get 3 or 4 stakes out of each $5-6 arrow - depending on how long you want the stakes. Then visit the hardware store and find some hardood dowel that just fits inside the shafts. A loose fit can be fixed with epoxy putty and a tight fit can be fixed by putting a short length of dowel in an electric drill and sanding it down. Glue short pieces of dowel the bottom of the stake with superglue or epoxy and cut the stake at an angle. A Dremmel or other rotary tool works well for that.
I cap the tops with gutted parachute cord. Just glue a strip of cord over the top. Then I wrap the cord around the stake, leave a 1" loop free, and wrap it some more, gluing with Superglue the whole time. The wrap of cord keeps tent lines from slipping off and, if you decide to add the loops you can put lines through them for an even more secure hold. Also soak the exposed carbon fiber around the point and about 1" up to keep fibers from shredding out.
Wanna try some other stuff? How about a graphite spoon? About 0.15 oz. is the lightest I can get, however.