
Save your money from you.
So here's a tip from the first hint of re-rolling for your future cataclysm Hunter (or other classes, but I'm just gonna cover Hunter). Everyday you can generally make money without trying. 400g a day isn't that hard to accomplish given just the bare minimum of dailies (and that's not counting what you vendor!) and let me share a little math with you.
Hey don't worry! I suck at math too, so I promise it's easy! ;)
Let's say that MMO-champion and other sites are right and Cataclysm releases in the Spring. Let's say March. That's 7 months from now. Now, since I never did memorize which month has 30 days and which has 31 days in the year, lets go with the 28 day (4 week) minimum. That's 196 days of saving up you can do! Now let's say you only want to save up 250g a day til Cataclysm comes out just for your re-rolled Hunter.
That's 49,000 gold you will have just for that re-rolled Hunter.
250g a day for 49k g?! That's insane, but it's also genius. Keep in mind when you re-roll,

So start saving now! Even if you save 100g a day, that's 19k you'll have by that same date. Still a nice chunk of change to set to the side.
Quick List:
Total Mount Training Fee*: 6,844g
Total Mount Costs: 161g
Again, these are just rough numbers to show how much gold adds up if you set aside even a small amount everyday.
*Counting Cold Weather Flying at 1000g