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QT famously had a dual, "non-commercial" and "commercial" licenses, before they switched to LGPL.

From wikipedia / web archive: https://web.archive.org/web/20031005175911/http://www.trollt...

Highcharts.js has a free-for-noncommercial, paid-otherwise license system

https://shop.highsoft.com/highcharts

(Not affiliated, but using highcharts for a project @ a non-profit)

gSOAP has a separate commercial use license. They use a mix of GPLv2 plus a separate license for companies that want to avoid having to relicense their own products under the GPL (as a consequence of the viral nature of GPL vs something like LGPL).