I picked up an ARC of The Burning Sky by Sherry Thomas at RWA. I love this prologue. I will, in the future hold up this prologue as a defense that I don't hate all prologues. But then, I felt it took a while for the story to get to the part the prologue promised. (Not forever, a day in book time, which is for some people not long at all and for impatient readers like myself - a bit of waiting.) But the book lived up to the promise and ultimately I really enjoyed it and look forward to the rest of the trilogy.
Iolanthe Seabourne is an elemental mage being looked after by a guardian slipping deeper into addiction. When he inexplicably tries to ruin a light elixir she is working on, she calls down a bolt of lightning to fix it, drawing the attention of those who have been waiting for a predicted powerful mage. Prince Titus shows up with a plan in place to protect her - she will come with him to his non-mage school in England (Eton) and act the part of his classmate returned from convalescence.