What sends shivers down your spine when you play it on your system?

Oooo Mahler! Lots to revisit there!

Is that Mahler symphony 6 or 5?

I have that from Symphony 5 on a Classical
music for yoga and meditation CD. Giving it a streaming now.  Quite lovely and mellow yet encompassing. 

Mahler Symphony #3 is my favorite of the ones I know well. It transports me to an alternate state of mind throughout its duration.

Debussy's Deux Arabesques performed by pianist Philippe Entremont on a lousy-sounding old Masterworks LP.  The choral movement of Mahler's Third on an I-wish-it-sounded-slightly-better Jascha Horenstein recording I have  on both Nonesuch and Unicorn LPs.  Des Knaben Wunderhorn on Vanguard. Mike Garson's piano solo on Bowie's Aladdin Sane.

I think twoleftears meant Mahler 5, which I agree is absolutely beautiful.  Staying with Mahler, I agree with Mapman on Mahler 2, the final portion of the last movement always gives me the shivers.  As does the third movement of the Shostakovich 5th Symphony.

Ralph Vaughan Williams: Sinfonia Antartica

Also, The chimes at beginning of The Cures "Pictures of You"...

"Monday Monday"
"California Dreaming"