Picotux is one of the smallest computers running Linux. There are several different kinds of picotux available, but the main one is the picotux 100. It is 35 mm × 19 mm × 19 mm and just barely larger than an 8P8C modular connector. Two communication interfaces are provided, 10/100 Mbit/s half/full duplex Ethernet and a serial port with up to 230,400 bit/s. Five additional lines can be used for either general input/output or serial handshaking.