If you haven't read "Starve a Rat" by Justin Torres, please do; it's wonderful. Published in the October 2011 issue of Harper's, "Starve a Rat" deftly uses first-person point of view to create a wonderful narrative that draws the reader in. Are we being lied to by the narrator? Definitely. Does he ever tell us the truth? Probably.
The narrator is basically homeless and sleeps with other men to get by. He's charming and attractive, but also manipulative. In the story he hooks up with an older man, Norwood, who cares for him on some level, but also is interested in using him, though it becomes difficult to tell who is using whom. There are truths Norwood wants to know, like does the narrator have a disease, and stories about the narrator's past, which seem fabricated, that Norwood is willing to accept. For the reader, we know more of the truth than Norwood, so it's a bit easier, but still ambiguous. The idea of truth and lies is clear in the following passage.
"My girl and I used to play a game called Two Truths and a Lie—but the trick was just to tell three lies, or three true things; the trick was to let no one ever really figure you out: Take my picture. Be my father. Let me stay right here."
This paragraph haunts the story as we listen to the narrator. Is he telling us three truths, three lies, or a combination of the two? It's up to the reader to decide.