Among the 11 proven practices for more effective, efficient peer code review, diff annotation seems to be the one particularly well suited to tool assistance. The article is written by the architect of SmartBear's CodeCollaborator, so he of course recommends using that. Does anyone know of any alternatives? I can't think of anything that would be even close to paper+pen+marker in pure developer efficiency when it comes to explaining a piece of code.
I use SmartBear's CodeCollaborator at work, and find it really streamlines the review process. I'd definately consider it.
There are also some open source alternatives worth investigating:
Reitveld - This Python based tool is loosely based on Googles internal code review tool (Mondrian).
Review Board - Another open source review tool