Over at Den of Geek, they have come up with a most unusual top ten list - companions of the Doctor who never were!
Carey Mulligan (Sally Sparrow, Blink), came out on top. Stephen Moffatt described Carey as "one to watch" - is easily the best of the bunch, despite appearances from Sara Griffith's Ray in Delta and the Bannermen (1987) and Isobel Watkins from 1969's The Invasion - a reference that draw's an interesting observation:
Ironically the Troughton era presented many a feminist role in the supporting cast yet the companions of the time (especially Victoria) were some of the most notable screamers in the series history. Despite a forthright rebuke of the Brigadier's chauvinism, Isobel is ultimately seen as merely company for Zoë whilst the Doctor and Jamie investigate Vaughan.