Don't Starve was originally created for a 3-day game jam, where it was simply referred to as a "creepy Castaway simulator". In its earliest stages, the player would wake up next to a fireplace and an axe, having to fend off waves of pig men that grew larger with each night.
When examining the fishing pole with Maxwell, he will say "I will eat for a lifetime." This is a reference to the saying "Give a man a fish, and he will eat for a day. Teach a man to fish, and he will eat for a lifetime."
According to Klei, there was originally going to be a Tesla Biome in the Reign Of Giants DLC. Not much is known about it, other than that it would have included Telsa Trees, and it would have been where Volt Goats originally spawned.
Being out in the dark for too long increases the risk of being attacked by an unknown creature. According to the game's files, this creature is called the Grue. This is a reference to the text adventure game Zork.
When examining the hammer with Wilson, he will say "Stop! It's time! To hammer things!". This is a reference to M.C. Hammer's song "U Can't Touch This".