Mesa Electronics 7i43: http://www.mesanet.com $80. The 7i43 is an FPGA-based "Anything I/O" board. It has a Spartan3 FPGA (200K or 400K gates) and 48 I/O pins.LinuxCNC supports this board with the HostMot2 firmware, which is available in many different configurations providing encoders, PWM generators, step/dir generators, and general purpose digital I/O pins.
