I put a couple of minimalist LED testers together out of junk parts for the space. 9V snaps harvested from dead 9V batteries, old but not dead 9V batteries, some female headers and resistors. The header and resistor are soldered directly to the connections on the snap and covered with hot melt glue. A layer of white-out makes the background for the polarity labels. These should be good to just have out on the table for circuit building or Arduino classes. We might even have a few around and leave them on other hackerspaces’ benches as a little branded present!
Sorry for the poor picture. Picturenaut failed me – I just couldn’t get nice HDR pictures like I did before.