Let me begin by stating this is not the only solution to preventing spam, but rather a compromise between annoying inputs (reCAPTCHA, math inputs, etc) and making forms more difficult for spam bots. I personally cannot stand having to input reCAPTCHA values, though, it is a proven technique for mitigating spam. If you are going to use Akismet, I prefer to use it as one of two lines of defense since it can produce false positives and doesn't stop unknown signatures.
Rather, I prefer the honeypot for small to medium-sized sites. It takes the irritation out of forms that also improves form conversions. Happy visitors, unhappy spam bots ;-)