Michael there are guest posts on the bs section. I believe once you have scrolled past the music threads you come to the bs section if you open a thread there and want to post a message then go down to the bottom where the comment box is type your message where it says From the site asks that people posting as guest use a consistent nickname.

If you want to start a bs thread I think that was banned for a while not sure if it still is but if you can start a bs thread to the left of where you put the thread title you will see a box titled Common Prefix if you press the arrow in this box you will see a drop down menu. Hope this helps