I've discovered that an easy way to flavor drinks is to take those 50-cent concentrated fresh-breath drops you get from Walgreens, and drip a few drops into my drink of choice. Peppermint, Wintergreen, spearmint; all make interesting changes to whatever drink you apply them to.

Another think you can do is take Mike n Ike's or similar candies and dissolve them in your drink of choice. Careful! They cause a lot of fizzing, and the pop may be a little flat afterwards. You'll also want to drink it, or remove the gummy candy cores, before the cores disintigrate. While the cores don't change the flavor, they add a wierd texture. (They also look funny after a while, which makes them a great, safe way for grossing out friends.)

dont try to mess with perfection. Try flavoring seltzer instead, its a rather nuetral starting point and leaves room for flavoring. Good rootbeer dosen't bad rootbeer it won't make good.

Flavoured Coke works because Coke has a relatively neutral flavour to start with. Root Beer has such a distinctive and strong flavour that adding other flavours would a) spoil it and b) taste horribly wrong. I like my root beer to be root beer flavoured, not some artificial "fruit" flavour!