Boards
People who don't even try to spell correctly or punctuate.
I just got this reply to an ad I placed on Gumtree to sell an Ipod Nano.
"hey sir i am very interested in your product can i come pk it up any problems with it and would u meet me in centrqal london"
Even if I hadn't already sold this, I feel I would ignore this person on the grounds that in he has made no effort with spelling, punctuation, or even bothering to write whole words.