Perhaps the only stealth that is still not unethical is the stealth of knowledge, and SciHub is sure about this. It just so frequently happens that you need to get an article, but the article is paid. SciHub is made to break these paywalls. The following are the steps to get an article free on SciHub.
Find and Copy the DOI or PMID (See below) of the article.
Go to SciHub.tw and paste your PMID or DOI then click Open.
Disclaimer: I do not encourage you to violate any copyright laws. Please respect your local laws; you are responsible for that.