If you need to create a simple screencast but don't want the hassle of installing and configuring software, ScreenCastle gets the job done from any Java-enabled web browser.
ScreenCastle is a dead simple screencasting tool. Visit the website, click the big red button, and ScreenCastle will load a small Java control application—seen to the left here. At that point you specify if you want the whole screen to be recorded or a portion you select, as well as whether or not you want audio from your computer's microphone to be included. Those are the only two settings you'll be using, once you make your selection a black bar appears at the top of your screen with a record button on it and the instruction to touch your mouse cursor to the top of the screen when you are done recording. If you're not recording the full screen, you'll have a focus window with a stop recording button on it. Check out the screencast below to see ScreenCastle in action. Total time from loading the website to creating to the simple screencast to embedding the link here was barely over the length of the screencast itself:
There is no limit on the size or length of your recording, but keep in mind that the file will be uploaded from your computer when you're done so lengthy sessions will take longer to upload. Each screencast is given a unique URL and when you're done recording you'll be given a list of formatted URLs you can use including a link to the Screencastle player, an HTML embed code, and a direct link to the file in case you want to download it it. There is no way to edit your screencast so you'll have to live with mistakes or start over, a small trade off for the extreme simplicity of the service and free hosting of your screencasts. ScreenCastle is a free web-based application, a web browser with Java Script support is required. ScreenCastle [via Webware]