Wimpy handshakes. Especially those wimpy WOMAN handshakes, where the woman in question sorta does the limp-wrist flop, as if I'm supposed to bow over her hand and kiss it or something.
It's probably my German upbringing, but I can't stand a bad handshake.
Maybe I should start a class? Proper Handshakes 101. Or write a book..."Shaking Hands for Dummies."
Works for me.