Ask HN: Are there any non-email spam/bot detection SAAS providers for websites?

I've come across umpteen homegrown implementations to detect spam comments/signups ranging from point thresholds, cookie checking, javascript injection, css hiding, timeouts...

Also, people are paid to solve captchas.

Then you have the problem of abusive bots which can be resolved by honeypots & fail2ban, but you have to make sure your logs are aggregated, communicate the firewall rules to your web proxy and then be careful of blocking search engines.

You can also integrate spam blacklists and keep them up to date.

If there aren't any existing providers I'm starting to wonder if there would be an opportunity to create a saas offering which:

* allows developers to integrate simply by plugging into popular web frameworks, protecting not only comments but user/beta signups, etc.

* automatically uses all the best methods for stopping spam & bot abuse, both client and server side, automatically improving its own algorithms

* maintains and automatically distributes a central, real time blacklist database

* provides a great interface for monitoring/reporting and to easily blacklist or whitelist

ps. I had the unfortunate experience of having my submission link timeout as I wrote this submission :)