The talented Karen from Sew Karen-ly Created asked me about knitting socks two at a time on one needle. I learned this technique from the book "2-at-a-time Socks" by Melissa Morgan-Oakes, I have also seen it called the magic loop method. It is on one long circular needle (recommended at least 100cm, but I have also used shorter).
It is a very easy technique that allows you to make both socks at the same time (2 balls of wool, or one working both ends), so the socks are identical (same number of rows for the ribbing, leg etc.). Any sock pattern will work in this method. I am currently working on a pattern from the book in the picture, called Twilight. Sorry they are hard to see in the picture but they are grey because I thought I should have a sedate pair of socks in my wardrobe. Usually I use self patterning yarn in bright colours, because it is fun to knit with, and shows the progress well, but it is not always appropriate to wear.
I use to knit socks on 5 (sometimes 4) needles, and the nice thing about this method is you change needles less often, so it is faster. The needle doesn't tend to fall out, you don't loose needles, you don't need to finish a row before you put your knitting away. But, the best thing of all you don't get excited about finishing one sock and realize you still have to make another one!
The pair I am working on is in Patons Kroy, with 2.5mm needles (the wool is in separate bags to stop them from getting tangled). I hope people give this method a try, as it is easier than the 5 (4) needle method.