Inspired by this thread in /r/trees. A little Googling reveals that the first small gas-powered lighters appeared in the early 1800s. Several online articles mention that modified flintlock pistols were once used as lighters, but I can't find a source for that. Are there any examples of portable lighters (not continually-lit lamps, but devices that only ignited a flame when needed) before the gas-powered ones came along?
Hand-drills and bow-drills used friction to start fires. They were definitely portable and definitely ignited flame when needed (obviously not as quickly or as easily as a modern lighter). They are at least 7,000-10,000 years old and almost certainly much older than that (fire as a technology goes back at least a half million years).