I feel your pain. I had a transcon the other day which the middle seat was filled at the last moment (standby, I guess) ... with a lady who absolutely reeked of cheap perfume. Yuck! Six hours of stink.

I've also had a few unfortunate UX flights where my seatmate apparently doesn't understand that modern convenience which is deodorant. (One one, it was actually the woman one row behind me, who complained about her seat assignment the entire flight--I bet the person next to her had a much more legitimate complaint about seats!)

Unfortunately, these things are part & parcel of travel, and for that matter, society at large.