Wi-Fi (802.11 wireless Ethernet) access points have been around for awhile. But most of them allow rather limited programmability, especially if you want to make a business out of selling highly customized ones.
Chipset maker Intersil <http://www.intersil.com/> has walked into this marketplace and taken care of the opportunity problem by introducing with a new self-hosting access point reference design called PRISM AP. What makes it so marketable is its operating system: embedding Linux. PRISM AP comes with a whole Linux development environment on which you can run a Web server, a DHCP server, DHCP client, SNMP server and a telnet daemon so you can log in and run all your standard linux and network tools and utilities. Among other things.
And because the OS is Linux, you can customize units for your own uses, or develop whatever product you like -- gateway, bridge, router, mesh network, whatever -- and burn the code into flash memory. Then you can sell it without worrying about licensing costs.
In other words, it's hard to imagine anything more equally hackable and marketable, or in more different ways.