Great post by Stefan Thies about how he used Crate and Node.js to overlay the raw data from website log files with whois information, enabling him to "name" visitors to a site.
Data enrichment - overlaying data or the addition of metadata - is a known technique that can support anything from the use case in Stefan's post (assiging a "face" to site visitors) to fraud detection and security applications. It is definitely worth a look.
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