Robin Good: InFocus.cc is a useful and free web app which allows you to select/highlight any area on any web page, and get a shareable URL for it.
This is very useful for when you need to tell someone where to specifically look on a web page without having to draw a small manual for it.
Here is how it works:
1) You input the URL of the site where you want to highight a section
2) InFocus.cc takes you that web page and it provides you with a trasparent, draggable and resizable selector that you use to define the area to highlight.
3) InFocus.cc provides you with a URL that you can share with anyone to show that specific page/view and the section you have highlighted
Here is an example: http://bit.ly/inFocus-example
Free to use.
Try it now: http://infocus.cc/