A lot of the time, I like plain knitting. If you have a self-patterning yarn, or if you are doing something with stripes, or if you just want a simple sweater to throw on when you run out to rake leaves, plain knitting (that is: stockinette stitch) works well for that.
Stockinette is also good if you're watching something absorbing, like a movie with subtitles you must read. Or if you're invigilating an exam and really need to be watching the students rather than what you're doing with your knitting.
I have a couple pairs of plain socks going. The top sock is "Sausulito" (Crystal Palace, I think?) in the color Simply Sock Yarn named "Jam and Toast." The bottom sock is an Opal yarn, from their "Polarlichten" line (supposed to mimic the aurora borealis). It's a heavier yarn, essentially a dk weight, so it's knit on fewer stitches (and it knits up faster):
Even with "plain" socks, you can vary what you do. The Toast and Jam socks have a twisted-stitch ribbing (you knit through the back of each loop, rather than the more typical through-the-front). And the Polarlichten socks have a deeper ribbing than I usually do. And there are a whole bunch of different combinations of ribbing you can do if you want to do ribbed socks - 1x1, 2x2, 2x1, even up to a 7x1 (which I've used a few times - not for the cuffs, but for the leg of the sock). And then there are things like k3, p1, k1, p1, where you get a rib that varies in width.
But it's also good to knit fancier things sometimes. And granted, the socks I'm showing here are easy, as far as "fancy" goes - I have a couple pairs of twisted-stitch socks I am working on off and on (mostly off) that take a LOT more thought and a lot more time.
But I like these socks; they please me for several reasons.
First, the pattern just looks nice knit up. The book I am using as a stitch library here ("Super Stitches Knitting") calls it "Traveling Fern" but I think it exists under other names elsewhere.
**I** think it looks like feathers, which is why I am calling these my Pegasus Feather socks. Especially since I am knitting them of a color that is ALMOST Rainbow Dash Blue. The yarn is Knitpicks "Glimmer," there is a tiny, hard to see strand of tinsel-like stuff mixed in with the yarn, so there's a little shine there.
I'm doing these subtle - but if a person wanted to be more openly Brony about it, they could do the cuff (which is just six rows of in-the-round garter stitch (in other words: purl one row, knit one row) and the heels and the toes in a rainbow variegated yarn.
Or you could use a soft yellow for Fluttershy (I actually already have a pair of delicate yellow socks in a "fern and cable" pattern, and again, the ferns look like feathers to me). Or grey, for another favorite pony (And maybe do yellow heels and toes. Or work an intentional mistake - a "derp" - into the socks). Or a variegated orange for Spitfire. Or even lavender and pink for Rainbowshine, a background pony you see occasionally....
Here it is stretched out over my hand; you can maybe see the sparkle there a little better.