At the lighthouse, Hurley asks Jack to let him know when the dial reaches 108 degrees. When Hurley starts to pull the chain to rotate the dial, the chain is a well used one. In the next shot (closeup of pulley/gears), the chain is a brand new chain.
Jack's appendectomy scar is shown to be on the lower left quadrant of his abdomen. The appendix, however, is located on the lower *right* quadrant. In Something Nice Back Home (2008) Juliet took out his inflamed appendix and she performed the surgery at the correct site, i.e. on the right side of the abdomen.
When Hurley inspects the corridor in the temple, the writing on his arm reflects the light in a way that ordinary ink of any kind wouldn't, revealing it to be a glossy decal. It was easier to apply a decal of the whole text for each day of shooting instead of writing it on Jorge Garcia's arm.