A couple GMs are writing about how they run things -- how their sessions are physically set up. I first found it through Barking Alien's writeup of his style. This is what I do.
I sit on the floor. When I write about RPGs I always refer to what happens at "the table," but in reality I'd rather sprawl out. The floor has a lot more room for dice and books and, crucially, the long long legs that come from being 6'4". Players sit in a loose circle on the floor, the couch, the recliner, wherever. Keep it casual. In someone else's house, a decent recliner with a small side table does the trick.
The battlemat (hexes on one side, square grid on t'other) is standing nearby in case I need it. I probably won't, since I like to run a description-light game with few maps, but it can be handy if you want a tense tactical throwdown.
Character voices are gonna happen. People who don't like to deal with voices, or watch me do facial expressions as I lurch around the room, should go find a different hobby. I hear that the model train people are pretty docile.
I like a GM screen to hide my dice and my behind-the-scenes maps, but it's not essential.
My notebook, however, is crucial. That's where the notes are. I'm pretty good at making it up as I go -- better than most GMs, perhaps -- but you still need the notebook to write down what happened. A good group will surprise you a half-dozen times every hour; save those memories.
Plus someone will invariably want a map of Where Everyone Is, and it's a pain to get out the battlemat and the markers and do all the post-map cleaning just for a quick sketch. The notebook suffices.
I'll need liquids within arm's reach. All that voice-acting and lurching leaves me with a raw throat.
One downside of the floor-based GM style is that the dog will want to get involved. This requires a certain caution with the deployment of dice, pencils, and my well-loved Marvel Super Heroes cardboard minis. But if you all sit at the table, then the dog gets whiny about being ignored, and the whining is much worse than the occasional pencil theft.
Yes, we'll probably order pizza. No, we're not some stereotype. I just like pizza.