Advertising is a wonderful thing. Where else can you be as creative with such a large microphone? By microphone, of course, I'm referring to the whatever medium is used to get your message across. Also, where else can you promote absurd product advantages...things like "drinkability"?
Some people in the industry are perfectly content doing work for local non-profit accounts. Others head to the big cities with the big buildings, aspiring to work on the largest mega-brands in the world.
But I'll let you in on a little secret that most advertising people don't know: the biggest and best brand that you will ever work on during your career is yourself. Think about it. It's the only brand that you have complete control of. You are your own media planner, account director, copywriter, public relations specialist, and owner. You are an agency of one.
Everything you do, from office hallway interactions with colleagues to e-mailing your friends and family, define your personal brand in some way. Every one of your actions influences the public perception of who you are as a person and as a brand.
Some personal brands go through re-branding, and that's okay. Sometimes you need to freshen your look or personal philosophy (think tagline). Just keep your focus on the things you can do today to strengthen your personal brand. Make yourself memorable and make yourself indispensable. But above all else, make sure that at the end of the day you can easily buy into what you're selling to others.