I've recently been trying Siggi's (Icelandic) yogurt & like it. It is super-thick, like Greek yogurt but more so. The carb count on the fruit flavored cups is low (11 grams), with very high protein.
Warning: it is made with small amounts of sugar.
I'm fond of Kalona Supernatural organic cream-top yogurt. It's low in carbs and, fortunately, lacks the chemical aftertaste that comes with artificial sweeteners. Thanks for the Siggi suggestion.
I have eaten the sugar free one and added fruit etc... it was pretty good but I went back to fage-I like the taste better. I think Siggi's has more strains of probiotics.
I make homemade yogurt. Icelandic yogurt (Skyr) is actually a cheese since rennet is added. You basically make a yogurt and then add some rennet before fermenting. Once fermented you drain the yogurt in a cheesecloth and you get very thick curds. You can drain plain yogurt, that is what is called greek yogurt, but the result will have a creamy consistency rather than the bite of Skyr. The sugar is added to tone down the sour tangyness of the yogurt. I don't think traditional Skyr uses sugar.
I never buy Greek yogurt, I always use my yogurt strainer overnight to make beautiful thick yogurt. The one I have is white plastic, it's the 32 oz yogurt stainer from Progressive, I highly recommend it. I like Stoneyfield yogurt.
Siggi's got me again. In love with the new mango-jalapeno flavor.