Did anyone mention the Linux Cross Reference (Score 1)

I found taking the time to snag the code and index it for the LXR allows you to click through functions quickly without needing any special C-scope type application etc. http://lxr.linux.no/ I like it since it's web based and you can plow through code from anywhere in your work area (any computers that have web access to the server w/ LXR on it). I used to create a cron driven script that would grab the source from source control once a night and index certain key versions of the code we were working on to make it readily available.