Years ago, I switched our little Linksys/Cisco router out for a RaspberryPi configured as a firewall/router. I noticed an immediate jump in the speed of my home network. It also allowed me to set up scripts to automatically block our kids' internet access during certain hours, and a lot of other neat capabilities that simply aren't possible with most out-of-the-box routers.
I've been upgrading RPis as they are released.
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