A dodgy looking fellow (or fellet) usually holding a pregnant gerbil and suffering form a interned eye. also talking very loudly on the phone on trains and quiet public places. Fuckwits are most famous for sending you and E-mail then immediately phoning you to tell you they have sent that email, then discussing with you the content of it. Hence there being no point of sending it
"hello steve im a fuckwit"
"pardon me sir but your a fuckwit"