http://redpill.booru.org - this category and that site has pages and images focused on Anonymous political culture. Overall there is a politics focus; although sometimes there is a focus on philosophy and other semi-unrelated stuff.
Here is a good place to search these tags: http://archive.4plebs.org/pol/
Pages in category "Redpill"
The following 200 pages are in this category, out of 2,324 total.