The question is: could Akismet be used on email? And could something like Amazon’s Elastic Cloud help in this respect?

But seriously, email spam is pretty hairy and tackling it would be a pretty significant departure from what Akismet does. I don’t forsee us moving in that direction anytime soon, though I’d be lying if I said I haven’t considered it when dealing with the influx of email spam that’s been getting through lately.

1. In my experience, blog comment spam just isn’t that sophisticated, compared to e-mail spam. Almost every comment spam Akismet has caught for me has the same exact format. E-mail spammers seem to do a better job of looking exactly like a legitimate message from a friend or a company you do business with.

2. False positives are less devastating in blog comments. If someone wanted to say “nice job” or offer an insight, nothing too bad will happen when that comment gets eaten by the filter. But in e-mail, the thing that gets eaten could have been an important receipt, a license code, or substantial correspondence from a loved one.