I love writing in busy places. I write on trains, in cafés, at airports. It's something I do a lot.
Part of why I enjoy it is because I can squeeze my writing into the little cracks of my day. Between writing at lunch, and on my train rides, I can get almost two hours of writing a day done, when I'm focused.
There's also this hard to explain thing that happens when you write in busy places. The atmosphere of the place becomes a sort of alpha-wave-stimulating background noise. I'm sitting at an outdoor café as I write this, and listening to traffic go by, to the far off sounds of construction, and seeing people walk down the street. It's like all that busy-ness is leaking into my head, being processed by my brain, and coming out through my fingers into the fiction I'm working on (not to mention this blog post.)
I know other authors groove on this too. J. K. Rowling wrote huge chunks of Harry Potter and the Sorcerer's Stone sitting in a café, scribbling on big yellow legal pads. My friend Zorro, an incredibly prolific ageplay erotica author, carries around this little notebook, and it's not uncommon to see him curl over it, almost protectively, as he scribbles away in it furiously, when inspiration hits him.
I forget sometimes, and then become blissfully aware and grateful for how much I enjoy the process and discipline of writing.