Maxs released this package a few days ago and has now written a tutorial for integrating it, as well as a little back story:
“Honeypot” method of spam prevention is a simple and effective way to defer some of the spam bots that come to your site. This technique is based on creating an input field that should be left empty by the real users of the application but will most likely be filled out by spam bots. In addition, this package implements a requirement for the user not to submit the form too quickly. If the form is submitted within few seconds from showing it to the user, it is likely a spam submission.