Here's the rundown:
1) loli, shota, and toddlercon images are blocked for users below Gold level (regular Member users). Members can still see posts from those tags that they uploaded themselves.
2) Please do not ask for special exemptions or anything like that.
3) You get invited by contributing to the site. Tag edits, new posts, translation notes, programming help, etc. Don't ask a mod for an invite, that will have the opposite effect. The mod will find you if they want. You can also donate to obtain a privileged account. See here for details. See also forum #7207.
4) These are the only tags that are blocked.
I'm locking this to avoid more of the same old debate, but if I missed anything that would be useful in this post, please PM me and I'll add it.
Edited
- 2008-07-25 to update list of types (contributor, janitor) in point #1.
- 2009-06-30 to clarify it applies to shota as well and mention the donation approach.
- 2022-10-21 users can see their own restricted uploads now
Updated by RaisingK