"Hey, I'll sue Satan!" is an infamous phrase spoken by Frank Sinatra in the reversed version of his song "Summer Wind". It was uncovered by Ben in the Oddity Archive episode "gniksaM sdrawkcaB (Backwards Masking)", where after the reversed phrase is played he quips, "That's right, I'm gonna sue that little red bastard for everything he's got, and I especially want those sweet horns!"
In reality, the phrase has no meaning; it's a product of the forward lyric "And guess who sighs his lullabies?". The word "and" tends to sound like "-tan" as in Satan played backwards, "and" is immediately followed with a word ending with an S-sound, and "who sighs his" explains the first three quarters.