I was thinking of the Mayans this morning, and the controversy about the Mayan calendar in 2012 (through a long and circuitous thought process). But it got me thinking: Someone back 5000 years ago built a calendar which planned ahead 5000 years.
Lots of sci-fi books, stories, and movies are based in the future, and many of them have specific dates - Star Trek is mostly in the 23rd and 24th centuries, for instance.
This got me thinking... what is the latest date ever for the setting of a sci-fi story? I'm specifically ruling out time travel, unless a specific date is given. Vague 'millions of years in the future' like in H.G. Wells' Time Machine or a similar PK Dick story aren't really what I'm looking for, so they aren't relevant. May consider time travelers from the future if a specific date of their source is given (i.e. no "I'm from the 31st century, hello!" - not specific enough).
I'd consider just a year, or even maybe a small range of years, close enough, but no more vague than that.