More of your conversation would infect my brain.
They have a plentiful lack of wit.
'Sblood, you starveling, you elf-skin, you dried neat's tongue, you bull's pizzle, you stock-fish! O for breath to utter what is like thee! you tailor's-yard, you sheath, you bowcase; you vile standing-tuck!
1 Henry IV (2.4.227-9)
Thy food is such
As hath been belch'd on by infected lungs.
Thou sodden-witted lord! thou hast no more brain than I have in mine elbows.
Troilus and Cressida (2.1.41)
Here's one for writers:
Thou hast the most unsavoury similes.
1 Henry IV (1.2.75)
This Shakespearean Insult Generator will toss some random Elizabethan insults your way.