Cal Newport has a great book on the topic: "So Good They Can't Ignore you" [1]. Might be worth taking a look at, or at least Derek Sivers's book notes on it [2]
Particularly of interest might be his discussion of Self-Determination theory [3]. According to SDT, motivation requires autonomy, competence, and relatedness. In the workplace, this translates to have control over your work, being good at your work, and being connected to co-workers.
[1] http://www.amazon.com/Good-They-Cant-Ignore-You-ebook/dp/B00...