If you flatten the seventh note of the major scale, you get Mixolydian mode.
Mixolydian is a medieval mode that fell out of favor with "art" music composers during the Baroque era. However, it stayed alive and well in various European folk traditions before having an explosion in popularity during the rock era, helped by its resemblance to the blues.
Here's an interactive walkthrough via the magic of Noteflight.
Music in Mixolydian
"India" by John Coltrane is in G Mixolydian. Coltrane was deliberately trying to invoke Hindustani classical music, as the title suggests.
"Tomorrow Never Knows" by the Beatles is in C Mixolydian. This tune also shows the influence of Indian music, through its pedal bassline and tanpura drone.
The ending section of "Hey Jude" is in F Mixolydian.
The Grateful Dead love Mixolydian, and based many of their open-ended jams on it. "Fire on the Mountain" is in B Mixo.
"Once in a Lifetime" by Talking Heads is in D Mixo.
Madonna's "Express Yourself" is in G Mixo.
Björk's "Big Time Sensuality" is in E-flat Mixo.
"Royals" by Lorde is in D Mixo.
What do these tunes have in common? They have simple or nonexistent chord progressions, influences from non-Western cultures, and a certain simultaneous ancientness and modernness. Mixolydian is a versatile tool.