in reply to
How should I do (and document) effective semi-formal code review?
You might like to look at a web-based code review tool. Guido van Rossum's first project at Google was such a tool, called Mondrian. Though he was unable to open source that work,
he has since released the open source
Rietveld code review tool.
I'm also aware of the similar-looking
Crucible, sold by Atlassian.
Though I've not used any of these tools yet,
I may look into using one of these in the coming months.
That said, I do enjoy the face-to-face communication of a code review meeting,
and would personally not like to lose that.