This excellent tutorial was originally created by troy512. Send some +rep his way.
This app does get overlooked, but its very, very, useful and people need to use it. Nintendo Update System Downloader, or NUSD, is a PC Utility designed to allow easy access to the resources present on Nintendo's Update Servers. Using this tool, you can download, pack, and decrypt many system titles into WADs ready to install.
The database included in the downloads is dated Sept. 21/10 (note: the DSi common key.bin file is NOT included)
To manually update the database.xml file, copy the hidden text below and paste it into the database.xml file, overwriting the older text. Or, delete the old database.xml file, create a new text document and name it database.xml, and do the same.
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