The OpenWrt Project is a Linux operating system targeting embedded devices. Instead of trying to create a single, static firmware, OpenWrt provides a fully writable filesystem with package management. This frees you from the application selection and configuration provided by the vendor and allows you to customize the device through the use of packages to suit any application. For developers, OpenWrt is the framework to build an application without having to build a complete firmware around it; for users this means the ability for full customization, to use the device in ways never envisioned.- [Text taken of OpenWrt website].
Since 2011, there has been a close collaboration between OpenWrt and FreeWear, that donate a portion of the sales of OpenWrt materials in this website.
Donations accumulated until 2022/12: 275.75 € (VAT included)
More information: https://openwrt.org/
OpenWrt stuff available right now:
OpenWrt friends organic t-shirt
OpenWrt organic t-shirt
OpenWrt fitted t-shirt
OpenWrt white sticker
OpenWrt navy sticker