Another member helped me creating one of the most useful REGEXP that i use so far:
From this:
Röyksopp - Beautiful DAY withOUT yoU (Rex The Dog Remix)
To this:
Röyksopp - Beautiful day without you (Rex The Dog Remix)
USING:
Action type: Replace with regular expression
Field: TITLE
Regular expression: ^(.*?)((|$)
Replace matches with: $caps3($1)$2
[ ] case-sensitive comparison