One thing I sometimes need to do is record what's going on on my desktop, a.k.a. 'screencasting'. It's an ideal way to make demo videos for clients or to talk someone through a process. Until now I'd used Snapz Pro, the big daddy of OS X screen recording software, but now I've discovered that iShowU is now a lot better.. and it's priced right too, $20 versus $69. The biggest improvement over Snapz Pro is that iShowU is really fast. It compresses the video on the fly rather than making you wait forever afterwards. You can also pause recording and resume.