Soldato
Rosberg's attitude is just awful, and I think he's actually tarnishing the team in a way that other number 2 drivers (eg Massa, Webber, Irvine, Coulthard, etc) never did when they were consistently beaten by faster team mates.
Webber was *always* whinging when he was getting whipped by Vettel (or team orders).
Coulthard came consistently high up the WDC standings - plenty of 3rds and a 2nd in 2001 when Hakkinen was nowhere near him - definitely not the sort of 2nd driver career that Webber had even though Hakkinen was clearly the better driver of the two overall. Not sure I'd put Coulthard in the same group as Massa, Webber, Rosberg etc personally.