Harvest Moon - Did You Know Gaming? Feat. PeanutButterGamer
It's possible to give wine to the character May, who is a little girl. Doing so will result in her saying "This is very pretty! Keep it a secret from Grampa..."
Contributed by CosmykTheDolfyn
The sign for The Hospital misspells "hospital" as "hospitel".
Contributed by CosmykTheDolfyn
Turning on the TV on Friday the 13th results in there being no news.
Contributed by CosmykTheDolfyn
If the player decides to tell NPC's about a job at the winery, speaking to the town's priest, Carter, will result in the choice to do so being written in German. If the player does tell him about the job, Carter's response will also be in German.
The player's two options, when translated, are:
"Tell about the Job."
"Don't tell."
When translated, Carter says:
"A part-time job at the winery sounds like a lot of fun."
Contributed by CosmykTheDolfyn
There are three unused items left in the game's code: the Band-Aid, the Queen of the Night, and the Plant Encyclopedia. All have their own description and are worth 800 affection points when given to a girl.
Contributed by ClaudX
After talking to Zack a few times when he picks up your shipment, he will speak Japanese. The text says:


Translated to English it says:
(Hey) [Name],
It's become a pretty nice farm, hasn't it?
From the way things look, it's pretty admirable.
Contributed by ClaudX
There is a glitch that be seen using a clock and the TV in your home. Purchase a clock, wait until the time is 4:40, and enter your house. Examine the clock, and if it is 4:44, go to the TV and interact with it. The text box will repeatedly open and close until the game has been turned off, and back on again.

This glitch was turned into an easter egg in More Friends of Mineral Town where the number 4 appears repeatedly on screen given the same circumstances.
Contributed by PheonixGRX