In most cases I like using cookies to remember returning users to my websites.
In my early/foolish days, I would store a UserID (auto-increment integer) in a cookie and if the user returned I would use that cookie value to log them in automatically. This was a bad idea because someone could easily edit the cookie to use a different integer and log in as someone else.
Is it ok to store a UserID in this same manner if the UserID is a GUID?
What are the best practices for storing "remember me" cookies?