The transformers, capacitors, and diodes are always valued by HV enthusiasts. Mind you, they are lethal (when powered) if precautions are not observed. The magnetrons aren't usually that valuable and can be tossed unless you want the ceramic ring magnets inside. If you do go after the magnets, avoid damaging the protruding bit, as it has a beryllium based insulator. If you get in contact with the dust from a broken beryllium insulator it can cause berylliosis and/or cancer (and not a low chance either!).