Ticket 51: Use The Mixolydian Mode

The Mixolydian mode is a major scale with a b7th. In the key of A

A B C# D E F# G

Chords

Amaj Bm C#dim* Dmaj Em F#m G maj

A 'happy' scale but not as saccharine as the major scale (Ionian mode). The relative freshness of the scale often frees up songwriters to use just two or three chords to make their point.

*In practice the C#dim is often replaced by A/C#

Paperback Writer
Rain
She Said She Said
The Inner Light
Tomorrow Never Knows
Within You Without You

also

All Right Now (Free)
Best Of Both Worlds (Van Halen)
Celebration - Verse (Kool And The Gang)
Ever So Lonely (Monsoon)
Highway To Hell (AC/DC)
In The Light – intro (Led Zeppelin)
Summer Song (Joe Satriani)
Sweet Home Alabama (Lynyrd Skynyrd)

And much Indian and Country Rock music.

See also

Ticket 28: Use At Least One Out Of Key Chord
Ticket 40: Don't Use All Seven Notes Of The Scale
Ticket 63: Write With The 'Other' Scale
Ticket 68: Use the R b7 6 b6 Progression

See the full list of songwriting tips here - Tickets To Write