  Interactivity, experimenting and performing laboratory practicals contribute
much to the efficiency of natural science and engineering education. Computers
represent a natural element for today's students, thus the use of computers in
experiments may engender considerable enthusiasm amongst them. Here we
introduce two open-source, compact USB-based data acquisition devices, which we
have developed for the purposes of education. These instruments offer
connectivity to various sensors, like thermistors, photodiodes, sensors of
acceleration, pressure, magnetic field and many other physical quantities, and
provide both digital and analogue outputs.
