What do you mean by "a lighter"? If you mean a butane-fuelled disposable lighter, I doubt you could fit one in your wallet. But you could probably glue some lighter flints to an old key and store that in the coin pouch. I carry a credit-card sized plastic Fresnel lens (a flat magnifying glass) along with my credit cards and driver's license.
I haven't tried it personally, but I believe some people here have stored a "Military Match" successfully in their wallets. That's a very compact magnesium rod with a flint striker built into the side (I think).
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"The mind is not a vessel to be filled but a fire to be kindled."
-Plutarch