In What can we do to advertise Latin.SE?, I mentioned the possibility of creating community promotion ads for other sites. An ad for our site is currently one of several ads in the rotation on Christianity.SE, and is generating an average of about 4 visits/day.
Sites can only accept community promotion ads if they have graduated, so sites like French, Spanish, and Linguistics are unfortunately not possibilities. However, English Language & Usage.SE is a good option – many of its users have an academic interest in English and etymology, and it gets nearly 20 times the traffic of Christianity.SE.
So, who has an idea for an ad? It ought to appeal to English language experts and enthusiasts, especially those who might also have an interest in Latin. Here are the technical instructions, along with some existing examples. Two key parameters are 300x250 or 600x500 pixels and either a colored background or a border.