One of my favorite apps on Ubuntu is ScreenCloud. This is a simple little program that resides in my menu bar at the top of the screen and lets me take screenshots and store them on the web. Since I use this primarily for my blog, I can then copy the URL of the image to WordPress and be off on my way.
Above you can see what the admin page on the website looks like with all my screenshots. Below is the Preferences dialog. I’ve been using ScreenCloud for a month now and so far have not found it lacking any features and it performs perfectly.
If you’re looking for a nice, feature-rich screenshot capture program, look no further, ScreenCloud is there for you. Oh, it works on those other OS’s too.