Need to get a line up a tree

[RockRaven]

29. If you want to skip trial and error from throwing/slinging, AND you've got

the following materials, this method may be worth a shot. I've done it in the 30-40 ft range, should work for higher too. Works easiest from nearly directly under the branch, not from way off to the side.

Tie a weight to the end of a rope/cord. A full roll of duct tape or a full water bottle should be heavy enough.
Thread the rope through a 10 ft section of PVC or ABS pipe. Hold upright, keep hold of rope too so weight isn't pulling rope through.
Onto the free end of the rope thread on a straight coupling. Dry fit to end of pipe. Now slip on another pipe section, and dry fit that to the coupling. And the next coupling, etc.
Repeat until desired height is reached. Reach weight over and beyond branch in question. Slowly let out rope. Weight should pull rope through.
Once weight is on the ground, carefully disassemble pipe sections without losing control of the free end of the rope. Now you have a rope over a branch.

The higher you go and the skinnier the pipe, the bendier it will be. There is some limit beyond which it won't be easy to hold or control. And the most obvious downside -- requires materials which you may not have lying around.