TP-Link WR703N is a tiny 802.11N 150 Mbps Wi-Fi router smaller than a credit card (5.7 x 5.7 cm) and 1.8 cm thick based on Atheros AR7240 processor with 4 MB flash and 32 MB RAM. It costs just above $20 US and can be hacked with openWRT. It features one USB host connector that allows you to connect USB devices (USB flash drive, printer…) to it.
- Atheros AR7240 CPU @ 400Mhz (MIPS24k core)
- Atheros AR9331 Chipset (integrated wireless)
- 10/100 Mbit Ethernet port
- 802.11 b/g/n 150Mbps
- 3G support via external USB dongle
- 4 MB flash memory
- 32 MB RAM
- USB 2.0 port
- micro-USB port for power
- Dimension – 5.7 x 5.7 x 1.8 cm
All you need is a USB to TLL board to access the serial console, open the box to access the serial pins (TP_IN and TP_OUT) and follow the instructions on openWRT website to convert it into a Linux router.
You can do all sort of things with this board such as an home automation system, a printer server (there may be limits to the document size due to the lack of memory), a sensors gateway and more. It is powered via USB and only consumes 0.5W on average.
The router is available for $23 including shipping on Dealextreme, Aliexpress and eBay, and comes with a power supply and a micro USB to USB cable. You can get further information on the device on TP-Link website (in Chinese).