Apparently the newest craze in the Decentralized Finance (DeFi) sector is yield farming, where investors shop around for the best interest rates to get the most bang for their buck. This has been made possible by an explosion in platforms which offer crypto lending and borrowing, in combination with platforms like Coinbase which show the interest rates of each DeFi platform and allow users to choose. 

First some background info. DeFi sites allow crypto users to lend their crypto and receive interest in return, similar to a savings account at a bank. This interest is much higher than the rates that banks offer however, and often in the 5-10% range, and therefore there has been an explosion of people using DeFi to accrue interest. Indeed, there are now billions of dollars of funds invested into DeFi platforms. 

The site DeFi rate is the epitome of a tool that yield farmers would use, and it shows the different interest rates for different platforms. 

For example, for USDC deposits, Nuo offers 11.42% interest at this time, BlockFi offers 8.6%, dy/dx offers 1.67%, and Compound offers 0.1%.

Also, there is also a significant variation in interest rates between cryptocurrencies. For example, while 11.42% is the max interest rate available for USDC, the max interest available for Dai is only 4.45%, and the max interest available for Bitcoin (BTC) is 6%.

Notably, these interest rates fluctuate all the time, and the whole point of yield farming is to catch optimal deals right when they happen. 

Thus, the explosion in the DeFi sector, and the proliferation of DeFi platforms, has led to the rise of yield farming where DeFi investors constantly monitor all of the DeFi platforms in order to find the best interest rates, and this strategy can be quite fruitful since interest rates vary significantly between different DeFi platforms and between different cryptocurrencies.