If you are a literal boomer or have known one for a long enough, you probably know that there was a time when a "high interest savings account" truly was a savings account which was guaranteed to give the depositor a high rate of interest.  Rates as high as 8 or 10 percent were not unheard of.  Suffice it to say, with this sort of return depositing money with a bank was a very straight forward way not only to escape the ravages of inflation but even to see it grow over time.  Of course, those days are long behind us.

However, with the advent of bitcoin and other cryptocurrencies, something quite similar to those glorious high interest savings accounts has emerged, namely centralized financial platforms (CeFi).  While the high interest savings accounts that banks used to offer all those decades ago, CeFi platforms allow you to earn high rates of interest on crypto that you deposit with them.  Under certain circumstances, these rates can be very high indeed.  Let's take a look at a couple offerings.  Note: these lists are not exhaustive.

Midas.Investments: https://midas.investments/burnout?p=BahQkxL7v7
Bitcoin (BTC): 6 - 16%
Ethereum (ETH): 18 - 21%
Litecoin (LTC): 4 - 11%

BlockFi.com: https://blockfi.com/?ref=5f93b276
Bitcoin (BTC): 5%
Ethereum (ETH): 4.5%
Litecoin (LTC): 5.5%
Chainlink (LINK): 4.5%

Nexo.com:
Bitcoin (BTC): 4 - 8%
Ethereum (ETH): 4 - 8%
Litecoin (LTC): 6 - 8%
Chainlink (LINK): 6 - 8%
Ripple (XRP): 4 - 8%
Stellar (XLM): 4 - 8%

Celsius:
Bitcoin (BTC): 3.51% or 6.20%
Ethereum (ETH): 5.05%
Litecoin (LTC): 4.08%
Chainlink (LINK): 3.00%
Stellar (XLM): 3.10%