While playing around with the Stack Overflow data-dump, I was getting a feel for the schema and data by looking at my own posts and comments, and I happened coincidentally to notice my comment on this answer which turns out to have been popular. However, I had no idea until I stumbled upon it in the dump.
Shouldn't the profile page be a way to find everything that a given user has posted, be it a question, answer, or comment? I recognize that comments are definitely not the primary focus, and I wouldn't want to encourage commenting just for the sake of getting voted up (the comment in question was a drive-by comment that I never gave a second thought to until now). However, it would be nice to have a record of my past comments, or to be able to view comments of other users at a glance.
I think, in particular, the comments would be most valuable (or detrimental) to those using Stack Overflow et al as a resume since comments tend to illustrate a user's temperament and civility when dealing with others much more so that questions and answers which are often more carefully worded and edited.