Is it worth it??

I mean, there's no harm in letting your computer idle and mine cryptocurrency. What's the worst that could happen (assuming you don't go for any dodgy software) you don't get that much cash? Alternatively (it has nothing to do with crypto) if you want to donate your computer's processing power for a good cause, check out Folding@Home:

"Folding@Home is a project by the Stanford University that uses our computing power to help study the process of protein folding so as to aid research on various diseases, including many forms of cancer, Alzheimer's, Huntington's, and Parkinson's. It is basically a big distributed supercomputer, and you can contribute a node!"