How do you navigate being assigned to uninteresting projects?

I work as a sort of scientific programmer and am well paid for what I do. However, when I joined the (medium size) firm, I was assigned to a project that is somewhat interesting but ultimately unrelated to what I'm both good at or interested in. I figured that I should learn these new skills and it would get more interesting over time, but it's mostly led to a lack of interest in work and envy of my coworkers who are in groups that work on "sexy" projects.

I asked about transferring, but I got the impression it would "reset" me experience-wise, and didn't seem guaranteed to give me interesting work. On the flip side, I have a great boss who I am reluctant to leave because that's pretty rare.

I'm sure this is a common feeling. Is this just a case of "the grass is always greener" or should I consider finding something new? How do you navigate these kinds of questions for yourself?