UsbVia is small board that exposes USB contacts to allow for easier multimeter measurements. There are four 2 mm connectors (two for current and two for voltage measurement) that allow for direct multimeter probe connection.
Differences between releases
Latest C revision is 45 x 24 mm and allows for comfortable placement of four multimeter probes. Earlier B revision offers same functionality but you might find it a bit crowded because of its smaller size.
Release A has no connectors at all and you are expected to hold leads in via while test is in progress. This gets boring very quickly so I cannot recommend this for anyone.
Getting board done
While you wait for your PCBs to be ready, don't forget to order parts.
How to measure
Set multimeter on current measurement range and place its leads in lower two connectors. If you also need to monitor voltage, you can place second multimeter in upper two connectors.
In both cases you should place black lead on left to get positive measurement. If you swap leads, nothing bad will happen (other than all values being negative).