Ugh. IMO, guys look fine carrying one of the following:
- A gadget bag (laptop, tablet, etc.); should have a shoulder strap, and should be more about functionality and ruggedness than style. Should also be carried to and from work and left in the car when not purposely carrying it in somewhere. If you drive up to buy coffee and walk in with the bag with no real use for it, sorry, it's a purse.
- A briefcase. Not the gadget bags or satchels that people call briefcases these days, but a real, genuine briefcase. Rare, but still passable.
- A backpack. Self-explanatory. Doesn't look professional, hence the gadget bag or briefcase for a work environment.
- Nothing. Keys, phone, wallet, and that's it.
There's nothing wrong (IMO) with some other bag styles, like messengers (real ones) if the suit the individual's situation - for example, someone that bikes everywhere. I just find it stupid that some guys will carry a bag across their chest / resting on their hip everywhere they go and then get offended when someone calls it a man-purse.