A quick survey of prices for bottomless cups of coffee, by zip code:

• 98112 (Seattle, WA, Capitol Hill): $ 2.00
• 94117 (San Francisco, CA, Western Addition): $ 0.95

Venue options in the 94117 category include a diner where every mug is different, and at least one is hideously warped, bearing the inscription "I love you just the way you are: Imperfect."