Have used AdSense on latextemplates.com for 7 years. I wouldn't call it "good money" but it's a welcome addition to my income. Haven't noticed any drop the last several months, but 4 years or so ago there was a huge drop when they updated their algorithm.
I dislike Google and would love to move to something else, but everything I've tried is so much worse so I've just been stuck with it. Any suggestions?