inception: the implantation of another person's idea into a target's subconscious
Think about this for a second — another person's idea developing inside your mind without you ever realizing that your idea was never your idea to begin with.
Imagine a parallel universe or a not so distant future where this is indeed a possibility. We already live in a world of guided freedom; we need to dress a certain way, eat a certain way, speak a certain way so we are not frowned upon for not having the "society approved" etiquette on our foreheads. The only place where we are truly free to be ourselves is our own mind. What happens when your own mind becomes a host to inhabitants other than yourself? What happens when you are no longer you?
Long story short: a mind-fuck on steroids. If you leave your joint unattended after watching this, your joint will roll a miniature joint, spark it up and start getting all philosophical in your ashtray.