From my anthro MLP dreamscape. In that dreamscape the grownup CMC formed the metal band Flying Fingers! This has been a very successful band and has released several albums.
 
Scootaloo is the guitarist and secondary vocalist. She goes by the stage name of Flying Fingers as well. Sweetie Belle is the bassist and is the lead vocalist. Applebloom is the drummer and provides support vocals. For various concerts or album the band will bring support musicians for it.
 
This is one of the outfits Sweetie Belle has worn on stage and has posed in for various promotional images.