There are a number of other great small-telescope projects in different areas of astronomy. The one closest to my heart is ASAS-SN (pronounced "Assassin") since it was the idea of the professor across the hall from me when I was at Ohio State and an officemate of mine was the one who spent much of his graduate career building it. The idea was to get a little telescope (like Dragonfly it's pretty much just a telephoto lens with a detector attached) and then have it look at ~1/3 of the sky every night. That way if a supernova goes off in a nearby galaxy (or there is some other transient) it's discovered within a few days. Just this month they published a paper on the discovery of the brightest supernova ever observed [1]. They currently discover more supernovae than all other groups combined (including amateur astronomers, who are a formidable force!).
There's another small-telescope project built to search for exoplanets called KELT (the Kilodegree Extremely Little Telescope). Since transiting planets are generally detected around bright stars (at least in apparent magnitude), telescope size is not so important for their discovery. In fact, having too big a telescope can be an issue because the host star is so bright that it saturates the detector. So far they've discovered (I think) somewhere around a dozen planets, though my favorite is Kelt-4Ab because it's in a triple star system (and also because I'm on the paper) [2].