So, I guess I'll come right out and say what the second Mystery Project was/is. I was test knitting again!
The pattern I was test knitting this time is Nebula (Rav link). We test knitters were originally given May 1st as it's release date, but we were just told that Nebula was a pattern for the Loopy Ewe Spring Fling! Cookie A mentioned that she'll be getting this pattern available online in May. While I don't have both socks completed as of now, I do have the Right sock finished and I'm a couple inches into the Left sock. This pattern is a lot of fun to knit, but it made me VERY, VERY happy that I know how to cable without a cable needle.