I pickled a batch of kale back in Fall 2010. I used the basic sauerkraut method described here: http://www.wildfermentation.com/making-sauerkraut-2/ (same guy whose books are mentioned upthread). Just subbed kale for cabbage since I had a ton in the garden, plus about two bulbs of garlic sliced into disks. For a crock I used a glass jar like this from Target, and happened to have a glass plate the right size to use as a weight. It was very easy. Washing, chopping and pounding all that kale was a bit of a pain, but my boyfriend and I made an evening of it and it went by fast. I think I let it ferment for about 5 days? I don’t really remember but I checked it every few days until it seemed zesty enough and then packed it in mason jars and stuck it in the fridge.
It came out pretty well. A bit intense for me, I could only eat a bit at a time or mixed with things, but my dad and sister went nuts over the jar I brought them as a gift. I was afraid they’d come to blows when the jar was 3/4 empty within 4 days. They were eating it by the bowl! The stuff I kept lasted in the fridge getting eaten bit by bit until the following summer with no noticeable drop in quality.
We had a hot fall last year and my kale crop wasn’t as abundant, so I didn’t make it again, but I hope to try again this year. The hot fall is significant because I don’t have a/c and there really isn’t a cool spot in the house to ferment when it’s hot outdoors. I really want to do cucumber pickles - I tried those in 2010 as well and ended up with disgusting slimy messes, perhaps due to heat or the cukes being overripe? If I end up with a big harvest of them this year I’ll try that.