Music in the workplace.

So today I put my music on whilst working and I'm trying to decide if it is increasing my effectiveness or if it is distracting me, I'm certainly singing along with most of them (Simple Minds at the moment) but I'm still working and have almost completed my to do list for this morning, so I guess that means it works. This therefore begs the question, 'why do most companies not allow music in the office? I reckon if the boutique grew big enough for me to employ lots of staff in an office environment, I would have music playing and would actively encourage singing along (and even dancing to the printer or copier). How many people would want to work for me? How many people would never want to leave work? Just need to get this Company to GROW! (Listening to Live & Let Die now, it's a bit dramatic!) Samantha