This should be the thread where you share you secrets, your tricks, things that have helped you along the way.
I'm gonna start with a little fill which I recently learnt whilst playing some Franz Liszt. It's really cool, and you can add it in many hymns and songs. Basically you play a crushed triplet making the middle the melodic note. It can be used to add a bit of flair, or 'vivace' to your pieces, but should never be overused.
Attached is me playing it. I do the first one slowly so you can get what I mean, then play you a couple of bars of Lizt, then kinda overplay it. As I say, keep it to the minimum, and you have an effective fill!