Two years ago I accepted the post of a pro tem moderator on Computer Science. At that time, and that's true for any new beta SE site, there were little to no users with enough reputation to moderate. So, what did we do? Edit, close, migrate, whatever the situation called for.
I used to read, edit and tag every single post on the site for about a year. I'm no longer able to do so, due to a rising amount of posts (yay!) and time constraints on my end.
Now we are in a pickle: everybody seems to be used to not having to community-moderate.
So, here is the problem: the set of tools moderators can use are all for immediate action. There is no way to vote normally. There isn't any way to delay or delegate a decision in a platform-supported way. So the choice always is: use the sledgehammer now or accept that a bad post may stay on (assuming you don't go revisit questions much), creating bad precedents.
How can we ease users into community moderation? How can we let them feel the need for action without having to let the pile of crap grow too high?
Here are some feature ideas I have for aiding in training/engaging your community. I do not claim that all of these are great, but they should give an impression of my perspective.
Allow moderators to flag a question to themselves with a delay.
Allows us to wait for post improvement and community moderation without the danger of forgetting (letting the question slip through). Upon reflection, this may be best implemented by a personal review queue and (time-delayed) "send to queue X."
Allow moderators to cast unbinding votes (maybe create a time-delayed flag automatically).
Shows other users that moderators think the question is unsuited and asks them to participate in the effort (review queue!). Current situation: a) question closed, no user action required or b) moderator tag-edits but does not close, hence user assumes the question has to be fine.
Give moderators special "flags" that move questions to certain review queues, optionally with time delay.
Allows to delegate, prompt users to action. Also great for uncertain cases.
Have a review queue for badly tagged (only one tag; no common tag; many new tags) questions. (Or extend the low quality queue thus.)
Most of my edits (that may create an impression of omnipresence, reducing the need for user moderation) are retaggings. Good tagging is important, but at this time users are not prompted to act on bad tagging.
Issue a badge for some number of close/reopen votes that were "sealed" by a moderator or 10k.
Encourage close-voting as long as it is supported by policy. It might cause the need for a moderator-only flag "Closed by five lower-rep users" to prevent abuse.
Add "discuss" to moderation tools on posts. It should allow moderators/10ks to send a message to chat (or a post on meta) that asks fellow users to discuss the post.
Easy way to notify users that action might be needed. Also encourages discussion.
Let us move comments to chat.
Long overdue feature; we should be able to move meta-ish and subject-related discussions to chat (both site chat and new rooms) without having to wait for the system to do its work.
Such features may become obsolete/undesirable later in a site's life cycle; I do believe, however, that some additional support by the platform would greatly benefit smaller sites.
Note: This discussion applies mainly to beta and maybe freshly graduated sites. Bigger sites hopefully don't have the problem and have less trouble with allowing some proportion of crap and/or offending some new users by seemingly hard treatment. Therefore, I ask you to focus the discussion on such sites; an answer stating "We don't need that on the trilogy" is not useful at all.