Vodka and diet coke. Yum.
Nah, I really do like it. It brings out the flavor of the coke. I also like flavored martinis, but they are a pain in the ass to make (or so says my lazy ass). Diet coke and vodka is easy, tasty and has very few calories compared to other drinks.
Since vodka doesn't really taste like anything (unless you're drinking it straight), you can mix it with anything you like and it's fine. Really.