Repeating posts?

Is there a way to post something and have WordPress repeat it indefinitely on the same day? Plugin that does this?

What I’m wanting to do: I run a website for a Macintosh User Group (computer user group for Macs). We meet every third Saturday. I would like to have a post that would repeat itself and date itself for every third Saturday. This way I wouldn’t have to post the same information every month.

Ideally there would be a plugin out there that would do this, as well as let the user specify to repeat the post every day, every month, at set intervals (every ten days, for example) and every year. It would be useful if you could also set it for less or more (hours, decades) but I wouldn’t imagine this would be very practical.

Thanks in advance!