I tried turning off the Captcha codes, but this appears to increase the volume of spam I get. So I'm trying something else: a Disqus comment system. I chose Disqus because I already have an account and it's easy to implement.
Please let me know if there are any problems. If you can't comment, let me know by e-mail: skepticsplay at gmail dot com.
If there are no significant problems, then I will stick with Disqus. And to reduce confusion, I'll likely switch my name to "trivialknot", to match my Disqus handle.