Neko Knits Curved Double Pointed needles.
You can knit socks, hats and loops with only 3 knitting needles! Two needles hold the stitches and the third needle is used as the knitting needle.
They come in three varieties:
CDP Sock - approximately 4" from bend to tip
CDP Hate and Loops - Approximately 4.5” 5.5” from bend to tip depending on mm of needle)
CDP XL - approximately 6" from bend to tip