picotux: “The picotux 100 is the world's smallest Linux computer, only slightly larger (35mmx19mmx19mm) than an RJ45 connector. Inside, there is an ARM7 CPU at 55 MHz running uClinux kernel 2.4.27 and Busybox 1.0. Two communication interfaces are provided, 10/100 Mbit half/full duplex Ethernet and a serial port with up to 230.400 baud. Five additional lines can be used for either general input/output or serial handshaking.”

gumstix - waysmall options: “waysmall computers are complete Linux systems that fit in the palm of your hand. each come in a case with MMC slot, USB Device plug and a power adapter. waysmalls come in way cool configurations.”