Well since its timely, I will add this.
Matt Kirk just completed his record unsupported hike of the AT, 2185 miles in 58.5 days. Here is his gear list
5.25 lbs. Technically not SUL if you are going to split hairs ,but thats with 7 oz of cell phone, charger, usb adapter, etc. He kept online journal and pics of the hike for validation purposes. And needed good light and batteries for night hiking.
His gear and approach, is SUL without a doubt. He needed certain items for a record setting hike however.