Tripcode Spellings?

I see tripfags with words in their tripcode and I was wondering how it's done. Could someone please explain it to me?

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Tripcode Explorer is a program that allows you to find words or patterns in tripcodes.

Tripcode Explorer, like all other tripcode searchers (Tripper/Tripper+/tripcrunch), searches by generating random tripcodes and then searching for your text in the results.
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See the following more info on customizing tripcodes.

http://desktopthread.com/Tripcode_Explorer/