As in, how much taco can I have in my wheel before I should worry? Right now my front and back wheels on my monstrous steel hybrid commuter each wobble perhaps 1-2 mm, enough to brush the brake pads ever so slightly if I don't adjust them periodically, say once a month. They are not perceptibly out of round yet.
I'm in a context where having them retrued is a stretch and getting new wheels is a BIG stretch. (unless super cheap, true wheels are available somehow).
I have a spoke wrench and got them down to 1-2mm out of true from what they were before, perhaps 5-8mm out of true. Then I read stuff about spoke tensioning and figured I shouldn't monkey too much.