CS2: CSModules: CSModule implementation of Lightbox JS
A CSModule that I've used myself on a couple of sites, but haven't seen much written about is Ken Robertson's CSModule implementation of the Lightbox JS image overlay scripts.
This module enables you to insert thumbnails of your pictures in for example your blog posts by a specific text part. When viewing this thumbnail in a blog or a forum, and you click on it, it shows a larger image in the middle of the browser window, and the rest of the web page gets darker. I don't know if that's a good explanation for it, but let me instead show it with a screenshot:

You can also try it and se for yourself what it looks like here. When you've installed the CSModule, you just use the text part and give it the ID of a picture in your CS Photo gallery.

It would be cool to have a CSModule like this, that could show pictures from i.e. your Flickr account, and also to be able to determine what size it shows the expanded picture as.
Read more at Ken's blog
[UPDATE]
Hmm...after writing this post, I took a closer look at Ken's blog and it seems he implemented the Flickr thing a couple of days ago. :-) Really interesting! Need to try that when/if he releases it.
[/UPDATE]