People that send messages (text or chat) before they are really done typing the message or finished the thought... sending a long string of messages 1 line at a time in rapid fire..
The king of douche-textery also send emails in this manner.
Dave: Hey whats up?
Dave: Want to go out tonight I was
Dave: talking to Amy
Dave: And she and her girls are going to
Dave: go to Maxwells tonight
Steve: What the fuck's up the douche-textery