Distance from Arduino UNO to LCD: How far? How far from the UNO can I place an LCD (the typical 16x2)? Assuming that everything that is plugged into the LCD comes directly from the Arduino (power and data). 

I'd like to mount the LCD on the wall at eye level, my "box" will be on the floor, close to a power source.
The actual distance depends highly on several other factors:


Wire thickness / current carrying capacity / resistance
RFI (Radio Frequency Interference) environment
Data rate that you write to the LCD (Maybe you are using an I2C or SPI backpack)


In general, even 5 meters is probably going to work if you use sufficient wiring, but try it and see.

You may also need to add shielding to mitigate RFI.