deCypher said:

...what do I do?

I don't feel like driving out to the store to purchase one, but I've heard vague rumors that you can accurately measure a shot by only pouring out of the bottle for a certain amount of time.  This seems rather fishy since this doesn't necessarily take into account the size of different apertures in alcohol bottles, but I'm rather intrigued as to whether there's any way to do this.

Any drunken nerds out there up to the challenge?

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H'okay, so the diameter of a 750 ml bottle o' Smirnoff is 6.5 cm.  Therefore a 1.5 fluid ounce shot requires lowering the amount of liquid in the bottle by about 1.4 cm. 

Qubit said:

Pour for one second at a rate just below when teh bottle gasps for air.  This will be about 1oz.

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