I've found that music can have a profound effect on my productivity. If I'm trying to get 'into the zone', the best music to listen to is music that I'm already

I've found that music can have a profound effect on my productivity. If I'm trying to get 'into the zone', the best music to listen to is music that I'm already highly familiar with -- ideally, music that I've listened to while being in the zone in the past. My theory is that, the same way a particular smell can bring back a feeling from our childhood, a song can bring back the feeling of being productive, and our minds more easily fall back into that state.