Vocore2 Lite a $4 OpenWrt IoT board
VoCore2 Lite is a open source OpenWrt linux computer with 580Mhz MIPS CPU and 64MB Ram. Size on this super IoT device is smaller than a coin.Board is based on MediaTek MT7688AN and have typical power consumption only 74mA.
VoCore2 is Full version of MediaTek chip and ships with 128MB of DDR2 RAM and 16MB of NOR flash, while the Lite version has 64MB and 8MB, which is half the RAM and twice the flash of the original. The Lite version lacks an onboard antenna, and has only one U.FL antenna slot instead of two. It also lacks the standard version's PCie 1.1 interface, a feature missing from the original. You can Order Vcore2 here .