For people that dont know they were massively popular in 2011ish and looked like this;

The owners usually used fences to block off the bottom two gralats for themselves so they would benefit (this was before you could actually lock gralats). Was a reeeaaaly efficient way of farming - would get gralats to gold in like 20 mins - because the more people that were in a house the more gralats spawn. Popular belief was that the more 'lag' there was the faster gralats grew, hence people spamming the chat and using the afk emote

Farming in general stopped being popular in 2012(?) when there was an update to farming and it got nerfed. Before then literally every patch of grass was used by someone horsefarming, and most of the time people were nice enough to not steal them - i remember making gold gralats in the snowtown resort many a time, and if i remember correctly somebody actually made a black gralat there once