Quickly pour a dollop of liquid nitrogen on top of the warm drink. It will boil furiously, and condense water from the air to generate a nice visual effect, with dense white heavier-than-air fumes pouring over the edge of the glass. It crackles and spits noisily, too. Present to your guests, CAUTIONING THEM NOT TO DRINK THE COCKTAIL UNTIL AFTER IT HAS STOPPED BOILING. You'll find that people are sufficiently amazed/geeked-out to obey your instructions, but it is worth repeating the instruction every time you serve it, even if they know the routine.
Oh yeah, what does Ice-Worm Cocktail taste like? Those who don't like it think = mouthwash; those who do think = refreshing and minty. Everyone thinks it is cold. Everyone likes eating the ice-worm.