WiFi radios have fallen to a price point where you have to be pretty DIY-obsessed to bother making your own rather than picking one up off-the-shelf, so we're all the more impressed by Gary Dion's effort. Starting from an ASUS WL-520GU wireless router, he threw in a USB audio adapter and a VFD display together with a custom enclosure to match the rest of his A/V setup.
The build owes much of its inspiration to Jeff Keyzer's DIY WiFi radio from back in 2008. The various parts have a DIY controller board keeping them all in check, and then the router gets reflashed with OpenWRT. The whole thing can be locally controlled with the front-panel knob and button, or you can log into it remotely over the network.