Coffee

From Discworld MUD Wiki

Coffee beans hail from the coffee plant. The bean itself is the pit inside the red or purple fruit (cherry). The plant itself is a tropical or subtropical bush or small tree with dark green leaves. Ground coffee beans can be used to brew coffee or as an ingredient in energy tea.

This is a rare bush which seems to be growing happily outside its native environment. 
On it are small red pods which resemble... coffee beans?

Eating a coffee bean will result in the opposite of being drunk. While this is presumably a cure for too much alcohol, the latter may also be a cure for too much sobriety.

Coffee beans can be found at the following places:

• Academy of Artificers garden in Sto Lat
• Various stores and stalls about the Disc