You can say anything you want. You can complain, you can congratulate somebody on a posting milestone, you can quote a saying from Shakespeare, you can say something about food, or sex, or mention you watched a movie, tell a joke, ask a question, or whatever. Of course normal code of conduct, etc. will apply.
ONLY 3 RULES:
1. To make this at least a bit challenging, you must post at least EIGHT words.
2. Your post cannot use ANY word appearing in the post above - NOT EVEN a, the, is, I, hypercholesterolemia, are, me, and, or, an, in.
3. If you're replying to a post that's a question, you likewise must not repeat even one word from the post above you. (The rule still applies, though questions can sometimes be asked in ways that make it difficult to avoid using a word from the question.) After answering the question, you may choose to include another random thought, but the no-duplicating-words-from-above rule still applies. Using as few as 8 words IN TOTAL for both parts of your post is OK.
I'll start with an example of what four posts might look like:
POST ONE: I live in a rural area, on a Macadam-paved road.
POST TWO: Have you felt horny during the past two hours?
POST THREE: I was frisky earlier, but that was around 2:00.
I think that computers are massive black holes, from which even time cannot escape.
(Consider the 12 words after "POST FOUR" to be the begining of my post, for purposes of the rules above.)
POST FOUR: Do you have any friend or relative who is fighting in Iraq?