The guidebooks will tell you that there's not much to see in Danang. They may have a point. Certainly, there are no big attractions, ancient monuments, or even much shopping, but Danang has that small town charm which makes people watching an enjoyable pastime, if you like that sort of thing.
There are, however, a few notable things to see in Danang. Your first stop should probably be the Cham Museum. This museum was built by the French and houses many find sculptures collected from the ancient monuments of the kingdom of Champa. There are usually several cyclos parked around the entrance, who's drivers will offer to take you on a city tour. I'm not a big fan of cyclos, but did take a driver up on a tour to see what else the city had to offer.
There are a number of significant temples in Danang, although none of them are really notable compared to those of Hue, or even the clan houses of Hoi An. One exception is the Cao Dai temple.
There's also a war museum in Danang. Out front are arrayed many rusting remnants of American war machines along with Soviet and Chinese armaments as well. The museum is in the grounds of the Ho Chi Minh museum, which is reportedly worth a visit, but was closed on my one day in Danang.
Another "sight" of interest, as well as a possible location where you may want to stay, is Bac My An beach, which some Americans might know better as China Beach. This is actually a very long beach stretching for several kilometers. If you're a "beach person" or just like five-star luxury, then you might consider one of the many resorts on Bac My An Beach your home base for visits to Danang and Hoi An.
Other nearby attractions include Marble Mountain, a large limestone outcrop riddled with caves variously used as Buddhist temples and VC hideouts.