One thing I've noticed over the years is that most comments on posts over a couple weeks old tend to be comment spam. Disqus makes it very easy to delete comment spam (you just reply to the email with the word delete), but even so it's a bit of work to keep old threads clean of spam.
So I've decided to close comments after a post is two weeks old. I hope everyone is ok with that. Please let me know in the comments if you think that's a problem.
If you have a disqus powered comment system and want to do the same thing, you can go into the settings page and select a time period for "automatic closing".
