Satiating my geek curiosity
fireball and
lightningbolt are, as one would immediately expect, taken. However, if you must have an attack spell username, "coneofcold" is stll free; and, somewhat surprisingly to me, "magicmissile" is available.
featherfall is taken, as well as
light (duh).
silence is, but "silence15" isn't, or any similar variation.
bless is, but not "curelightwounds" or the more abstract (and poetic) "curelight".
Even the extremes are taken, from cantrip all the way up to
wish (though not "prismaticsphere", which is kind of a stretch, I'll admit).
flamestrike, which is what I was thinking of in the first place, is a deleted journal.
polymorph is taken. Oddly, "geas" is not. Nor are "cloudkill" and "dancinglights", both of which seem entirely worthy of use.
I tried looking up "teleportwithouterror" (teleport, check) and "circleofprotection", just in case, but LJ tells me "malformed username." Perhaps there's a character limit the longer spell names exceed?