Leopard Gecko's sense of smell?

I was wondering tonight about how strong is a leopard gecko's sense of smell, or any lizard for that matter. I know snakes have a very good sense of smell but I was wondering how other reptiles measure up to that. Does anyone know?

Bosc monitors and other lizads of that species use their tounges the same way a snake does, so I would presume they have a great sence of smell, however my ojo does have trouble distinguishing between a finger and a mouse sometimes.
As for leopard geckos I've never really done any research into it, but I would presume they had a decent sence of smell.