Cool story, bro: when I was in the first grade, I was eventually banned from participating in my class's spelling bees because I kept winning all the time. The teacher tried to make things fair by letting me pick some of the words, but then there were complaints that the words I picked were too difficult. (For example, I tried giving "spring" before the class learned the -ing ending. Bah.) Don't believe me? When my best friend gave his man-of-honor speech at my wedding, that's the anecdote he chose to open up with. Good times.
Regardless of my spelling prowess, there are certain words that I just can never spell correctly on my first try. I don't know what it is. I try memorization, mnemonics, repetition...nothing works. I have a mental block. I'm sure I'm leaving some out, but here are a number of my most frequent offenders:
fluorescent (I think these two have similar issues)
insistent (why is that E not an A?)
For the record, when I hit spell check just now, sure enough, I'd missed a couple and had to fix them. All hail the mighty spell check. I would be embarrassed without it.