In another thread Kalleh says that "piffle" was one of her dad's favourite words.
I wonder why we have so many great sounding words that mean "nonsense".

Piffle.
Balderdash
Poppycock.
Baloney
Claptrap
Tripe
Rot
Tosh
Twaddle
Gobbledegook

Any others?

craziness
ridiculousness
absurdity
babble
bananas
bunk
drivel
fatuity
folly
foolishness
gibberish
giddiness
hogwash
hooey
hot air
inanity
jest
jive
joke
madness
mumbo jumbo
ranting
rot
rubbish
scribble
senselessness
silliness
soft soap
stupidity
trash

and, the ultimate,

bullshit

I've heard most of proof's, though they don't all mean "nonsense," do they? Like "stupidity" or "trash?"

However, Bob has some I've not heard of, such as "claptrap," and "tripe or "tosh," though "tosh," it says, is "chiefly British.

You are right, though. It is interesting that there are so many words for "nonsense." One of my favorite words is "balderdash."