Fully launched StackExchange sites can show community ads for anything their community chooses. There are premade templates for ads for Area51 proposals:
area51 ad http://area51.stackexchange.com/ads/proposal/61013.png
but they're perhaps not the best for betas, since they still say "proposal" and are pretty generic. Is the premade one good enough? Or does anyone have something they'd like to offer up as an ad for any sites interested in advertising for coffee?
For example, text on a simple image can look good. Here's one from space:
Here are the image requirements:
- The image that you create must be 220 x 250 pixels
- Must be hosted through our standard image uploader (imgur)
- Must be GIF or PNG
- No animated GIFs
- Absolute limit on file size of 150 KB