ARM microcontrollers are great for running embedded linux. This project got some power as it uses 2MB SRAM, Philips LPC22xx processor that runs at 60MHz, SD/MMC card slot, NIC 10Mbit RTL8019 Ethernet chip.
If you dare to recreate this project – here are Eagle files needed. Also you need to load uClinux in to RAM memory with bootloader and uClinux source code with proper MMC/SD and network card drivers. Once everything is set – you can run various linux based servers like http, smtp etc. and access them via your computer client programs like browsers, pop clients – you name it.