The hazard or, if you prefer, the muse of writing -

The name of the Muse of Writing, according to the ancient Greeks, was Calliope.  Actually, she was the muse of heroic and epic poetry.  Since I write historical fiction, I think that's about as close as I come.

I've been going hammer and tongs at a new project, and she has been with me every step of the way.  ...or do I mean that she has obstructed me?  Hm.  Perhaps that is a better choice of words...

The hard thing is that if you do write, you have to have a muse. 

...but do I have to have one that sits on my keyboard? 

Now all I need is Terpsichore (muse of dance) to tap-dance on my keyboard.  I suspect it's only a matter of time.