If it is anything, it would tourism... When I was there, alot of the sites were in Arab controlled territory especially, Jericho, Hebron, Bethleham, East Jerusalem, (The Old City - Arab Quarter), going up into the Old Testament Sites in Judea and Samaria.
There is also some agriculture... the Israelis have worked jointly with Arab farmers in producing a huge crop of citrus, etc.
Tourism and some agriculture...that ain't much. I guess we can't expect any useful and saleable labor saving inventions coming out of Yasserland anytime soon. Before there can be an economy, there has to be a market which encourages invention and competition.