I do that too , just not with stocks , but Copper , lead , silver etc , started, I dunno , maybe the 70's , I am a bit more selective about stocks, I put 3% into a 401k every two weeks , and since I am on salary it is the exact same amount.Stocks though , individually , I only buy really solid ones and when they are cheap.Otherwise no need to bother.....
I'm always buying something. Not the index, but a few choice stocks, yes. I don't find the market to be all that compelling, but I don't think it's super expensive, either.