The 10 episodes that changed the world (September 2006)

• 1. 1001 - The Return of Chef
• 2. 608 - Red Hot Catholic Love
• 3. 804 - The Passion of the Jew
• 4. 708 - South Park Is Gay!
• 5. 202 - Cartman's Mom is Still a Dirty Slut
• 6. 404 - Timmy 2000
• 7. 904 - Best Friends Forever
• 8. 502 - It Hits the Fan
• 9. 101 - Cartman Gets an Anal Probe
• 10. 912 - Trapped in the Closet

These were picked by Comedy Central. I found it here.
Ok lets see, I've see numbers 1, 3, 7 & 10. Outta those I'd have to say number 7 was the best. I don't think this list is in any particular order, but after I watch all these I'll list them in my own awesome order.

(And yes, this list is bulleted AND numbered. That's how serious it is.)