I am very free myself in using the current F-word. However, with reflection and desire to not have my kids sent to the principal's office, I have discovered what I consider to be a better and much more appropriate alternative. Because F*** isn't really a bad thing, most people would like it and actively search it out, right?
I found a word that is really that bad, that captures the essence of the exclamation. And best of all, it sounds the same. Thank you, Battlestar Galactica.
FRACK! FRACK FRACK FRACK! I do not want this thing! This SUCKS! FRAAAAAAACK!!!