Just wondering what pieces of music, or exercises you use as warmup when you begin a practice session, rehearsal, or performance.  Often I run through a few of the Wolfhardt etudes, playing them slow the first time around and then much faster the second time around. Other times I might run through the scales or play some arpeggios, slowly at first then faster and faster until I feel comfortable warmed up. As far as music pieces go I often play Mozart's Symphony 40 Mvt. 1 as a warmup. I play it at a slow tempo the first time round then repeat at a fast tempo. Of course I don't always play the entire movement as a warmup. Often just play a part of it slow then play the whole thing at a faster tempo.