As of right now I'm reading The Foundation Trilogy (pg.82) and completed already the following: I, Robot; Rest of the Robots.
One character that I've liked a lot in both books is Robotpsychologist Susan Calvin not only because of the job title and narrative position but also because I can relate to her characteristics. (And also because its finally a new kind of protagonist)
Not to mention the two engineers who's name I've forgotten (Powell?, ?)
Now I've been wondering is there any other book where Susan Calvin or Powell (2 engineers) makes an appearance?