I love this question! I have a couple favourites.
"I.G.Y" by Donald Fagen. It's about International Geophysical Year. The lyrics have techno-utopian visions:
"On that train all graphite and glitter / Undersea by rail / Ninety minutes from New York to Paris"
"Here at home we'll play in the city / Powered by the sun"
...even AI alignment (and anti-aging?):
"A just machine to make big decisions / Programmed by fellows with compassion and vision / We'll be clean when their work is done / We'll be eternally free yes and eternally young"
And I just find the chorus so uplifting and inspiring:
"What a beautiful world this will be / What a glorious time to be free"
"Well Rested" by Kero Kero Bonito. This has more of an environmentalist / "Mother Earth" theme. But it also has a more general longtermist theme of perserverence and ensuring civilisation is "well rested" (which I interpret as being wise and resilient). The final lines are especially powerful to me:
"We have survived a hundred apocalypses / Doomsday hasn't come yet / You cannot stop civilisation"
It's also just an epic song that gets me up dancing!
Not inspiring but fun and relevant:
Don't do love, don't do friends
I'm only after success
Don't need a relationship
I'll never soften my grip
Don't want cash, don't want card
Want it fast, want it hard
Don't need money, don't need fame
I just want to make a change
I just wanna change, I just wanna change
I just wanna change, I just wanna change
I just wanna change
I know exactly what I want and who I want to be
I know exactly why I walk and talk like a machine
I'm now becoming my own self-fulfilled prophecy
Oh! Oh no! Oh no! Oh no! Oh!