Do you miss the ability to download and keep software updates directly from the Software Update application? I sure do. So I wrote a Service (81KB download) for Snow Leopard that will download and keep a copy of all updates recommended by the Software Update app.
The service will download the updates, then copy them to a folder called Updates in your home folder. It will then launch Software Update and allow you to install the updates without re-downloading them. The Service itself is just two steps, and you can open it up and look at it yourself in Automator.
If you'd like to recreate this yourself instead of downloading, the two steps are:
softwareupdate -d -a rsync -PavE /Library/Updates/ ~/Updates open /System/Library/CoreServices/Software\ Update.app
Mac OS X Hints
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