For a quick pick-me-up while traversing the city, try Beanz Espresso Bar & Café at 38 University Ave. (tel. 902/892-8797), just a block from Province House. The espresso drinks are good, and they also sell pastries, sandwiches, soups, and other light items.
A block north from Beanz, Cedar's Eatery at 81 University Ave. (tel. 902/892-7377) is a locally popular spot for inexpensive meals. Lebanese dishes are the specialty: things like yabrak (stuffed vine leaves) and kibbe (ground beef with crushed wheat and spices). There are also sandwiches and burgers. They're also open late for Charlottetown, until 11pm -- a boon when you've got the late-night munchies.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.