We’re pretty sure we’ve made our feelings on Nirvana covers clear; in general, we’re against them. But rules don’t seem to apply to Joseph Gordon-Levitt, who has been consistently wonderful ever since the first time we saw him on 3rd Rock from the Sun. So, we’re not surprised that we actually find his cover of “Lithium,” performed earlier this week at Seattle’s Neptune Theater, endearing. Perhaps it’s because he’s so earnest, and perhaps it’s because his voice cracks a bit on the way into the first chorus. We don’t know. We only hope you enjoy it as much as we do.