You can add your own cookies (the file format is really simple, and there are many of them floating around the net). If you really need to have an RSS Feed for them write a short script which outputs a fortune cookie into such a file, and add it to your crontab.
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-- symlink.ch [symlink.ch]: YAGSS - yet another German slash si
/usr/bin/fortune (Score:1)
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symlink.ch [symlink.ch]: YAGSS - yet another German slash si