At Mental Floss, you can find a handy list of "old-fashioned swears" to use in your moments when it seems profanity is required.
The list is interesting, although I don't know if these words constitute "swear words" the way we think of them today. Many of them come from oaths that the speakers might have taken more seriously than we do some of the four-letters we sling around. But the author is right on target that overuse has robbed many of our current words of their shock value and power. When every other word is the four-syllable combo that implies the subject is Oedipus in full-on Jocasta-shipping mode, then a user loses the ability to use it to truly insult someone.
All he or she does, in fact, is show a vocabulary too limited to think of something new.