This subject's come up before. My answers are about the same:
1) From 1972 Tour: You Can't Always Get What You Want... the whole concert was first class but for whatever reason that's clearly the most memorable song from it. In a way, Midnight Rambler is prolly a distant 2nd.
2) From VooDoo Lounge: Not Fade Away... just a big, heavy, thunderous song with a slow build... GREAT OPENER... very memorable.
3) From Forty Licks:
A) Can't You Hear Me Knockin'
Midnight Rambler w/ Keith & Ronnie on b-stage
C) Back to Back: Sympathy for the Devil & Gimme Shelter
4) From ABB Tour:
A) Satisfaction on the B-Stage
Jumpin' Jack Flash encore...
There are alot of great live songs in memory, but these are "a cut above".
"It's just that demon life has got me in it's sway..."