New toy! Upon loading an image page, it will scan the categories of that image, and, for each category, show the last and next one in the order of "addition to the category" as a thumbnail. Sounds complicated? Have a screenshot:
http://www.magnusmanske.de/wikipedia/gallerypreview.png
I put it under [[MediaWiki talk:Gallerypreview.js]]. Installation instructions on the page: http://commons.wikimedia.org/wiki/MediaWiki_talk:Gallerypreview.js
(Now that I read it, "gallerypreview" is not exactly correct; catchy name, anyone?)
Besides the "pretty" factor, it has some practical uses: * Shows number of images in the categories (spot one-image-only categories) * Complains if there's no/only "trivial" (licensing etc) categories
The query.php interface won't give more than 500 results per category, so last/next information on larger categories /will be wrong/. If you find any more "trivial" categories, please let me know (or add them to the script, it's simple, really!).
Have fun, Magnus