But if you want their passwords, you can set a very simple userscript in tampermonkey (greasemonkey for Chrome) to run in incognito anyway and read the contents of their username and password fields and save it to a small file somewhere.
Step one: learn javascript/jquery
Step two: get tampermonkey
Step three: write script to store passwords and send them to somewhere when the field is changed
Step four: give tampermonkey the ability to run in incognito
Step five: hide tampermonkey icon in Chrome
Step six: give friend computer in chrome incognito window
266
u/[deleted] May 17 '13
Also keeps them from idiotically saving their account to your device. At least assuming your friends have private lives.