In 2015 I suggested we advertise our site selectively on other SE sites and people generated several ads to run on Science Fiction, English Language & Learners, Academia, and The Workplace. It's 2016 now, which means we have to submit ads again, but first we have a little work to do as the size requirements have changed.
Please use answers here to collect ads you would like to propose on other sites (graduated sites only). Indicate the site where the ad should run, and if you've already proposed it, link here to the meta post on their site so we can follow its progress.
SE Image requirements:
The image that you create must be 300 x 250 pixels, or double that if retina.
Must be hosted through our standard image uploader (imgur)
Must be GIF or PNG
No animated GIFs
Absolute limit on file size of 40 KB
If the background of the image is white or partially white, there must be a 1px border surrounding it.
An ad could link to our main site, to a tag, or to a specific question.
Let's get ourselves some more publicity. Can you help?