Fantastical, Magical, Powerful...Useless Solution

I remember vague bits of a dream I had...years ago, I think. Or, it was a series of dreams with the same theme. I can't remember anymore. But basically, the gist is that I learn a fantastic or magical ability, but I learn it while dealing with a very mundane problem where it wouldn't help.

Like an example, I'd be sitting in line at the post office or the DMV, or a place like that, and suddenly I'd remember or I'd learn the ability to cast fireballs and rain fiery death down on anybody who crossed me.

Which is great, but I'm still in line at the DMV, and since I see no point in murdering people, my newfound power is useless and I still have to wait for X number of hours.

Just my luck, right?