Most of the ideas I've been exposed to about what the future would be like were dreamt up at or after this point in history, when it was more clear what possible paths technology could take (e.g. hovercrafts, computation, time machines, etc). What might someone during, say, the Renaissance have thought would be futuristic, when Europe was becoming a bit more secular but technology was young? Are there any records of how people imagined things could change?
Leonardo Davinci's work and imagination is a good example of renaissance era contributions to what the future might have looked like. Illustrations of armored tank-like vehicles, flying machines, horseless carriages, etc. Have all appeared in some form or another in his illustrations. As it happens, much of his ideas actually made it to reality near the beginning of the 20th century with electric vehicles and actual heavier-than-air flying machines.
In Gulliver's Travels (1726) by Johnathan Swift, the main character is shown a complicated machine which contains all the words the operators' language and prints random combinations out endlessly. Students write down any sentences that are produced from this, believing this to be the most efficient way to learn "the arts and sciences". The machine is encountered during Gulliver's visit to the "Academy of Legado" a satirical take on 18th century scientific societies. The chapter also describes many preposterous experiments the scientists waste government funding on (e.g. attempting to figure out how to turn feces back into food). The expense of these pointless experiments impoverish the populace while producing nothing of value.
Most read this as an attack on the Royal Society [of Science] of his day, a government funded group of scientists who claimed they could solve national problems with machines and (admittedly, sometimes half-baked) experiments. Government funded science was a new idea at the time and Swift didn't think it was a good idea.
Of course, it turned out that Government funded science was a pretty good idea which would produce results and not impoverish the nation. The ironic result being that the modern reader of Gulliver's Travels, reading about a complicated "teaching" machine that contains every known word, which it can combine and print may think "Woah, he just described a computer!", when Swift's intention was just to invent the most ridiculous machine he could think of.
So, not really about the future, but it is about "possible paths technology could take."
P.S. Wikipedia has a great article History of Science Fiction, with a section "Proto-science fiction in the Enlightenment and Age of Reason" that gives many other examples. (Warning: Memoirs of the Twentieth Century is a total tease, don't get your hopes up.)