Rouspeteur,
Here are a few more to add to your list.
(Courtesy of my-son-the-Major)
~~~~~~~~~~~~~~~~~~
Got a full 6-pack, but lacks the plastic thing to hold it all together."
>"A gross ignoramus - - - 144 times worse than an ordinary ignoramus."
>"He certainly takes a long time to make his pointless."
>"He doesn't have ulcers, but he's a carrier."
>"I would like to go hunting with him sometime."
>"He's been working with glue too much."
>"He would argue with a signpost."
>"He has a knack for making strangers immediately."
>"He brings a lot of joy whenever he leaves the room."
>"When his IQ reaches 50, he should sell."
>"If you see two people talking and one looks bored, he's the other one."
>"A photographic memory but with the lens cover glued on."
>"A prime candidate for natural de-selection."
>"Donated his brain to science before he was done using it."
>"Gates are down, the lights are flashing, but the train isn't coming."
>"Has two brains: one is lost and the other is out looking for it."
>"If he were any more stupid, he'd have to be watered twice a week."
>"If you give him a penny for his thoughts, you'd get change."
>"If you stand close enough to him, you can hear the ocean."
>"It's hard to believe that he beat out 1,000,000 other sperm."
>"One neuron short of a synapse."
>"Some drink from the fountain of knowledge; he only gargled."
>"Takes him 1 1/2 hours to watch 60 minutes."
>"The wheel is turning, but the hamster is dead."
