I work near Cafe 59, so I go here a lot for lunch (at least, when the weather is nice enough to walk). They make the best salad I've ever had. Probably because of the lemon-poppyseed dressing--it's delicious! (I don't like vinegar, so I'm usually not a salad fan.) I'm pretty sure the dressing is vegan, but I've never asked. The corn & curry soup is fantastic (and definitely vegan). My favorite sandwich is the hummus sandwich (it's not vegan as on the menu, but I'm sure it's fine without the cheese)--I get them to add tomatoes, which I think makes it even better.
Thier coffee/espresso is also decent. If you are a fan of sickeningly sweet espresso drinks, then they have drink options that will make you giddy (otherwise, steer clear of anything described on thier coffee menu).
Cons: not open for dinner