One of the tools I really appreciate because it helps me enhance my communication is Jing. Jing has a free edition that supports both screen captures with annotations and video captures with voice!
What I really like about this tool is the ease of use and the lack of unneeded options and clicks to get your job done.
I use Jing whenever I want to create a new case using FogBugz. For example whenever I want to report a bug or ask for an enhancement, I may capture the part of the screen of the application, annotate and save it to attach it then to a new case in FogBugz or send it directly using Skype to the remote programmer.
Sometimes, I even capture a video showing how to reproduce a bug. Capturing a video with Jing is very easy because it does exactly what you need, nothing more and nothing less.
Here is an example FogBugz case with a Jing screen capture with annotations for one of our internal projects. We develop this application using DevExpress XAF which is a very good framework for developing intranet applications.
This way, I can write fewer words than if I hadn’t prepared the screen capture. I will also try to post a video capture example in the future.