usbLink is a USB to Serial Converter which can support UART port (TX/RX), 4x digital IO or 3x 10-bit ADC input.

iCP12A Sub-G DAQduino is a dual mode USB and 433MHz long range wireless  (100m) iCP12 board in Arduino form with 10x input, output, analog, pwm pins. Great tool for signals monitoring (as oscilloscope), data acquisition and circuit troubleshooting at 1mSec/Samples (USB Mode) or 1Sec/Samples (Wireless Mode).