Chef Jamie Oliver confessed that he wet an adult diaper and froze it, and then wore it (but cut a hole for his peen) while making love to increase the chances of having a boy after hearing that it's all about temperature.
This is the first time I heard of it and I find it really funny... but I guess it couldn't hurt to try it, if you really want a boy. Buy maybe somebody should have told him first about him and the wifey adding more salt to their diet first (or maybe he's already heard that!). And yes, I believe that one is an old wives' tale while the frozen diaper thingie isn't.
Now, I guess I should check if over there in Alaska, there are indeed more boys born than girls. Hehe.