On the Pulse album, you can hear almost the entire audience singing along to "Wish You Were Here", in tribute to Syd Barrett.
Roger Waters' speech at the end of "Outside the Wall" at London's O2 Arena, in his Wall tour, where David Gilmour played and sang on "Comfortably Numb", then joined Waters and Mason at the end of the concert:
"Thirty years ago, when Dave and Nick and I first did this...uh, with Rick...I was a rather grumpy person and disaffected with rock and roll audiences...and put young David to the test...BUT ALL THAT'S CHANGED! I could not be happier to be with you, and these three guys (points to Gilmour and Mason), and all thirteen of us here, (points to his backing musicians), and you tonight, thank you very much indeed!"
The fact that David Gilmour personally made sure Syd Barrett received his share of royalties after he left the band.
Any picture of Roger, David, Rick, and Nick smiling and having fun together. Especially with how after The Dark Side of the Moon was released, their friendships started to fade.
According to Ginger Gilmour (David's ex-wife): David and his friend Emo Moore were both living together and then one day Roger called up David. Sometime later, David came back into the room and was ecstatic about the fact that he was going to be playing in Pink Floyd. David and Emo proceeded to jump around the room in celebration. Aww...
Bob Geldof - who at first HATED Pink Floyd - somehow convincing all of the Pink Floyd members to come back together one last time for a short, 20 minute gig at the Live 8 concert.
After the publicity of the Live 8 reunion boosted sales of Pink Floyd's EchoesGreatest Hits Album, David Gilmour encouraged himself and the other members of the band to donate their earnings to the Make Poverty History cause, and for other acts on the bill to do the same, feeling that it was money which "should be used to save lives".
The reunion itself for that matter; the various members of the band had not been on great terms for decades. Waters even took Mason & Gilmour to court over use of the band's name in The '80s; it was said that pigs would fly before they'd play together again. They put some pretty large differences aside to do so.
A small moment: At the 2:08 mark of "Comfortably Numb" - which the band knew would be the last song they ever played together in front of an audience - just before David plays his first solo, Mason stops playing for a second to take his headphones off. If it's the last time they do this, he's doing so without the tech.
Also the group hug just before they left the stage for the last time as Pink Floyd
In 2003, Gilmour also donated a $3.6 million dollar mansion in Maida Vale that he bought, but never used, to the ninth Earl Spencer to be used as a homeless shelter.
Richard Wright got the biggest cheers from the audience when David Gilmour introduced him on his On an Island tour, as Gilmour reported on his website after Wright's death in 2008.
After Prince's death in 2016, Gilmour incorporated "Purple Rain" into a performance of "Comfortably Numb".
:"Thirty years ago, when Dave and Nick and I first did this...uh, with Rick...I was a rather grumpy person and disaffected with rock and roll audiences...and put young David to the test...BUT ALL THAT'S CHANGED! I could not be happier to be with you, and these three guys (points to Gilmour and Mason), and all thirteen of us here, (points to his backing musicians), and you tonight, thank you very much indeed!"