Code review now has some good tools like ReviewBoard. However, when it comes to reviewing written work, like documentation, proposed guidelines and the like, the market of open source tools is rather empty.
ReviewBoard itself is fine, but only if documentation is in revision control (as opposed to wiki) and only if your team agrees on reviewing raw material. The best bet I've seen so far is Django's online book which employs paragraph-wise commenting, but its source code is not really published.
Which tools do you use and which would you recommend for an open-source team?