Neck sockets!!
Also, you can pull most capacitors, but be sure you test them with a decent meter before you shelve them. The jury is still out on this - it takes a while to desolder and test them, but if you manage to throw a few in the bin that are the right value when you NEED them, that makes it worth while.
Obviously, the purity rings from any TV tube should already be with your monitor the tube went to.
Yoke - if the connector matches your arcade chassis and the yoke produces an acceptable picture with your chassis, I'd use it, and save the yoke from your chassis for future use / resale.
Speakers - some TV's have nice shielded speakers in them that could be useful in a small JAMMA test rig or even a cab that needs a blown speaker replaced.
Power cord - I cut and keep this. It's always nice to have a spare cord around. The other day I needed to finish up a degauss ring project, and I needed a power cord.
Speaking of degauss rings, you can pull that from the TV too, if it's one you think you can use.
If you're into a lot of tube work, you can pull the rubber yoke wedges and convergence strips you see as well.
Certain transistors are nice to grab if they spec out to ones you have needed before. Voltage regulators, HOT, etc.
When I turn in a TV to Best Buy for recycling, there's usually a burned tube in a box and not much else

Sure LOOKS like a TV, but it'll never turn on again......