Has anyone here had experience with fellowships, particularly from the DOE? I'm wondering whether or not they're worth doing. I understand they allow you to focus completely on research/courses, but they always come with some strings attached and typically require you to renew each year. For example, I'm looking at a DOE fellowship that provides a 36K stipend + full tuition and travel expenses, but requires you to renew each year (and potentially your renewal could be denied and you're left without funding), requires you to focus on research of interest to the DOE, and requires a yearly practicum of a three month duration at a DOE lab. On the other hand, you could just TA at your grad school of choice, which I understand is a pain in the ***, but at least your funding is guaranteed and you can work close with your adviser year-round, and you don't have to deal with the hassle of traveling so much, and worrying about pleasing some outside organization. Any opinions? I kind of doubt I'd get the particular fellowship I'm looking at anyways, but I can spare myself the agony of deciding to apply or not if I can convince myself its either a great or terrible idea.