Help find genes correlated with cancer, map the galaxies, or develop an open-source covid therapeutic. Whatever area of science you are interested in, there is a BOINC project you can participate in. Some of them (like the black hole database) will even credit you for your findings!
BOINC is a free app that runs on every OS (Windows, MacOS, Linux, Android) that enables you to volunteer your spare computational power towards scientific research.
BOINC has been around for decades and has produced hundreds of scientific papers.
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There are some cryptocurrencies that reward you for your BOINC work. Gridcoin is the most well known and has been around over a decade (they also reward Folding@home). I definitely turn a profit doing BOINC work in winter since I’m using the waste heat. The rest of the year is a little more variable.