If you have Word 2007, there is a really neat tool that will enable you to automatically summarise a lengthy document. I used it for my previous post: Are Underprivileged Students Better Off Without Computers?
You simply need to add the icon to your tool bar. The How-To Geek will show you how to do this. Then whenever you want to summarise a document, click on the summarise icon and you have a choice of options. For example, you can replace the article with a summary, place an executive summary before the article or highlight main points in the article. Besides being a great time saver for writing summaries, I find it useful when I have to read lengthy reports. If they are web based, I select the article, right click and select ‘text only’ paste them into Word and summarise.