What should I do / use to hang a hammock-type chair on my balcony concrete ceiling?

Question:Should resist at least 250 pounds. What kind of drill, hook, etc?

Answers:
Use a Star type concrete insert. You will need to drill a 5/8" hole about 2" deep with a carbide drill and using a hammer drill that you can rent. The star insert has a lead sheathe around it and you put it in the hole and with the tool supplied drive the lead down into the hole which seats it forever. Another good system is called Hilti inserts they work very well in concrete