Sunday is (intermittent) Sex Day!

A friend IMs me tonight complaining about other friends of hers recently getting knocked up or knocking somebody up. One couple used the sponge and no condom, and another used a condom but didn't pull out before ejaculation. My friend says that the only way to have sex and be 99.9% sure that there's no, uhm, aftereffects, is to use a condom but pull out before ejaculation. Then she told me, "You must post this to your blog!" And I wouldn't want to get myself in trouble...

I've never heard her pullout theory, though it makes perfect sense. But I also think it may take some of the fun out of sex. What do you think? And what forms of birth control do you prefer?