I was looking for some tent pegs for hard ground and found that they consist of a steel spike or nail and a plastic top. I decide to make my own using my other tent peg as a starting point for the head. http://www.thingiverse.com/thing:135548 I printed mine in glow in the dark PLA and used 6mm by 150mm round wire nails from Screwfix which cost £3.59 for 1KG which was 30 nails. http://www.screwfix.com/p/round-wire-bright-nails-6-00-x-150mm-1kg-pack/13869?_requestid=151245 These are a common size for nails in the UK so might be found for a better price. The heads are 6 grams each so 180 grams for a set of 30. At a plastic cost of £20 per KG its around £3.60 so giving a total cost of aprox £7.20 as set. Please feel free to mod or print a set but please don't sell them on. I will be off camping soon and will give them a go but with the English weather as it is I think I will be using my other pegs for soft ground.I printed mine on a reprappro mendel In glow in the dark PLA at 0.3 layer height and 40% fill . I have included a file for a single print and 10 at a time that will fit on a 140mm X 140mm bed. After printed I run a 6mm drill down the hole to clean it out and it fit nice over the nail. enjoy ;)