I'll start with Ratko Varda.

Seriously, does this guy really look like an NBA player ?
He played played a remarkable one game for the Detroit Pistons and posted his NBA career highs in points (5), rebounds (1), FGA (3) and FGM (1). He ranks among the all time best in Points per 48 minute with an astonishing total of 39.9 ppg.
Ratko Varda. You gotta love him.
My next candidate is actually stuck around longer and never failed to impress, even though it is not sure if it was actually his play that caused admiration. The Big Dog. Antoine Carr.
I have to admit that Carr actually wasn't that bad of a playerand actually played a rather important role in Utah's finals appearance in 98. It is just his goofy look with those sunglasses that made me remember him. He also has to be considered one of the "rebound shyest" players in league history, averaging only 3.4 in 20 mpg throughout his career.

Antoine Carr going up against Michael Jordan.