Those ads?

If you are talking about the ones below the discussions I say they are called "similar discussions". These discussions are discussions started by other mylotters but are related to the one you have started. I am assuming that discussions are arrange (1)chronologically, meaning the ones with current activites appear on top, and (2) by relevance, meaning the ones with the same tags as your discussions has would appear on top. You can use this to you favor by tagging your discussions strategically. When you use more general tags in your discussions, there is a greater chance that your discussions can be viewed by more mylotters.