what is the difference in cheap and expensive vodka?  Is it worth the
money to spluge when used with a mixer?  Is there any difference in the
hangover?

I drink Vodka to the exclusion of all other spirits. I've tried a
couple dozen varieties. My vote for the best Vodka, measured by the
absence of a hangover, is Ketel One: http://www.ketelone.com/

Ketel One is noticibly better than a couple of my other favorites:
Stoly's and Absolute, as far as hangover is concerned. As with any
drinking, it's best to switch to water near the end and hydrate
yourself well, and take an Aleve (works for 12 hours) just before you
retire for the night.

Good luck!

Not quite an answer to your question, but an interesting read on the
subject.  It's an unscientific experiment to determine if filtering
cheap vodka can make it taste better.

http://www.ohmygoditburns.com/

Enjoy!

This thread might be of interest to you:

http://boards.straightdope.com/sdmb/showthread.php?t=381081

You shouldn't take Aleve (naproxen), Advil (ibruprofen), or aspirin
with alcohol as it can lead to stomach bleeding.

Likewise, acetaminophen (Tylenol) taken with alcohol can lead to liver damage.


Your best bets to minimize a hangover is water combined with food
and/or a multivitamin.