Front
Back (apologies for my handwriting!)
The text of the postcard is
Dear Ellen,
Pew! Pew! Pew!!
Sincerely,
DumbFunnery.com
P.S. I’m guessing that’s what Curiosity is saying (it’s a good guess, right?).
Attn: Ellen (8/7/13)
August 7, 2013
DumbFunnery 
Comments on: "Attn: Ellen (8/7/13)" (2)
I found the “Pew! Pew! Pew!” way more funny than I should have.
Haha no, it’s always appropriate to laugh at that