Pool, swarthy, manly baristos who pull stiff coffee drinks from their lovingly abused beast of an espresso machine, a sunny stone courtyard with tree stumps and odd benches where locals squeeze their bums together smoking outside, even in the bitter cold. A Mile End Montreal institution. Olimpico serves what may be the epitome of Montreal lattes - there are lots of other good similar ones, but you get the sense while you're there that to bother with any other would be a ridiculous waste of time.
If you are postering, just ask at the counter if you can put your materials up outside, last time I was doing this they stamped the poster so it didn't get pulled down until after the event was over, which I thought was sweet move.