It looked like a bunch of different ads (at least a dozen or more that I saw), posted at intervals of 1 minute or less apart, for somebody selling black magic voodoo astrology witchcraft spells or something. Like I said, I didn't click on any of the posts, but the topic headings and the post previews (when you hover your mouse over the topic in the "New Posts" list) looked like that.
No, I don't think they would have done that unless I paid them to. Hmm, or maybe they were trying to make me think my computer was hexed so they could then offer to remove the hex for a large fee.
Whoever it was evidently got booted and banned before too long, but they were sure trying to flood the "Mixing Techniques" forum with as much of their spam as possible before getting banned-- two to four posts per minute, all of them apparently different (different headers, anyway), but all basically the same old same old-- lost loves found, curses lifted, incantations incantated, bosses and spouses and pets enchanted, ends of rainbows located, out-of-gas cars rejuvenated, etc., all for a tidy fee of course. I figured it was all going to be deleted as soon as the mods noticed and banned the spammer, so I was tempted to take some screenshots for posterity.