The MSR Core Tent Stakes are the lightest full-strength tent pegs currently on the market. Strong, durable and extremely lightweight.
MSR says:
The rugged and simple Core Stake was engineered as a lightweight anchor for use in hard ground.
Constructed of ultralight 7075 aluminum, it offers high strength and holding power, with the added durability of a solid aluminum head. A reflective pull loop allows for easy removal. Available in 15 cm and 23 cm lengths. Sold individually and as a kit of 4 stakes.
Came across this type of peg as supplied with the Easton tents - they have width which means more grip than simple wire pegs. I also noted a marked reluctance to bend - and I was camping on rocky ground - at only 14g these are an excellent choice for most applications.