No, not really. Well, in really bad cases it can help to completely unbuild the wheel and then bend the rim around with whatever brutal tools come to hand (put two books on the floor, put the rim between them like a bridge, and step on it... gently!) and compare it to a round and true rim after every bend until you can't tell whether it's getting better or worse.
That's along the lines I was thinking. Thanks for the additional tips. Other options of course, are finding a good replacement rim, or a new equivalent, e.g. Velo Orange PBP.