Thanks to a friend in China, I recently learned about a handy tool for taking custom-sized screenshots.
As you probably know, you can take a screen shot by simply pressing the "Print Screen" key. But this captures the entire screen, which often includes far more than you needed to capture.
Enter MWSnap, a small piece of freeware which allows you to press a button and simply draw a box around the part of the screen you want to capture. You can then simply paste it into a document or email, or save it as a JPG file.
If you are an inexperienced computer user, this is probably something you don't need. But for those who do... you can download it from Tucows.
For example, here is a screenshot of my MWSnap settings page. It's a handy tool if you want to be able to show people what you see on your screen, either to help them or to ask for help from them.