Glutanimate makes great videos that introduce the plugins (and he writes/maintains some of them, including imo the above two).
But the basic idea is:
Image occlusion - allows you to make a "cloze" using an image. I.e. you select 3 parts of an image to hide (by drawing something over them), and then you get 3 cards, one with each thing being hidden, then having to be revealed. That's the basic gist, and it's amazing, especially if you're studying something with lots of drawings (I usually don't, but e.g. anatomy is useful. And even I find uses for it).
Cloze overlapper allows you to easily create something that's recommended in the famous SuperMemo learning article. Let's say you want to memorize a song. You write the lines of the song, then the plugin generates cards which go:
Card 1:
Song name
[...] (you have to know the first line)
Card 2:
Song name
The first line
[...] (you have to know the second line)
And so on. So you're getting the context of the last line of the song, and then you have to know the next line.
This is the "standard" way to learn something like songs, poems, etc, but also useful for other ordered lists of things. Incredibly customizable btw (how many lines to show, whether to show line after as well, etc).
Other fun things:
Image Resizer - simply a button that allows you to paste a smaller version of an image.
Advanced browser - makes the browser way more awesome (specifically, it gives you the option of sorting by arbitrary columns).
Note: Anki 2.1 just came out, and most plugins aren't compatible yet. So it's a real question whether it's worth upgrading if you rely on plugins.
What I’d really like to see are the plugins available on mobile. Most days are spent looking at the laptop screen for too long and grinding out an Anki session on the same laptop often takes a large dose of willpower. Doesn’t stop me from loving it and using it, I just use it less than I would.
