I'm sorry if this sounds rude, but for the life of me I'm trying to figure out why this is posted on the Budget Board? This is where I come to find money saving tips for my trip to disney and I'm not sure helping someone pick a brand of vodka has anything to do with budgeting or Disney? Am I missing something?
I think some of the lower ends (think house brand at a bar) can be tasted in a mixed drink.
This is true. Using something like a Brita does improve cheap vodka's taste but I don't think it is cost-effective. Cheaper to just buy the better stuff.
Darn it, someone beat me to it. YES! Brita filters make an AMAZING difference. I drink vodka straight, and have had about every brand out there. For straight drinking, I like Absolut Citron the best... it finishes with a burst of orange, much better than that usual "fumes" feeling you get after a shot. My husband travels to Russia frequently, and makes a game of bringing me all sorts of "variety" vodkas... usually, the prettier the bottle, the greater the likelyhood of it taking the enamel off your teeth!
So whenever it's time to change the brita filter, I run through one of the bottles of vodka he brought me. Usually that cleans it right up and makes it fine... if not, I mix it.
And for the record, I can almost always taste the alcohol in a mixed drink, no matter what the brand. The only exceptions are the very very syrupy sweet drinks...
So, what makes this budget? Re-using old brita filters to save money on booze, of course! (Remember the saying--use it up, make it do, or do without!) We're cutting down on waste here!

Also, a person who's been imbibing has to stay home, therefore can't go out and spend money. (Yes, I'm aware that some do go out, and do stupid things, and end up very very out-of-money after the lawyers are done with them, but this is a Disney board, and I'm living in my fantasy world!)
Oh, and if they drink their budget booze at the hotel on their trip, that's less money they spend at Epcot!
ETA: oh, and if you find a "straight" vodka that's really terrible, use it to extract vanilla! Seriously, buy a couple vanilla beans at the store, split the with a knife, and let it set for a few weeks. It's fantastic, and pure, unlike the stuff labelled "pure" at the grocery store-- and even including the cost of the beans, it's still a great deal for such good stuff. So there, another budget tip involving vodka!