Don't be a space invader: Some women have no objection to "touchy feely" encounters, others are horrified by it. Touching can be a lovely flirty action, but should be confined to the arms or resting the hand just above the arms. Until you know more. Test the personal space by moving closer, noticing the reactions then moving back a little.

Once you and your personal space have endured the commute, you then have to contend with the army of space invaders that makes up the American work force. As the traditional office suite has given way to the almighty cubicle, a highly structured code of workplace space etiquette has emerged. But there's always one knucklehead who doesn't know when to back off.

"If someone's a close-talker, it makes me instantly not like them," says Andrew Adams, a 34-year-old Web development executive. At a previous job Adams had to contend with a chronic space invader. "It's the first thing you think about when you have to interact with this guy — how to take away his ability to get close."

The Snoring Spreader. This is one of the more insidious and devious commuters around. Usually spotted on the afternoon train going home, but occasionally found on the inbound. Begins to nod off as the train rolls out of Grand Central. As he or she falls asleep, the head rolls sideways, often making its final resting place on top of your shoulder. The legs begin to relax as well and spread a bit, usually encroaching on your part of the seat.