Use rel="nofollow" for specific links

What the Google help says:

How does Google handle nofollowed links?

In general, we don't follow them. This means that Google does not transfer PageRank or anchor text across these links. Essentially, using nofollow causes us to drop the target links from our overall graph of the web.

While there is no specific advice given to the usage of this attribute when linking to your own pages I, if I were Google, would see this as a method of self-promotion and I would penalise webmasters for attempting it.

I use it every time that I link to a page on tempusfugit.ca - This is not because I am saying that the pages are untrustworthy, on the contrary, I just have no reason to self-promote them.

It is interesting, to me at least, that when links are placed in comments made on this blog the nofollow is added automatically. This is not documented, as far as I am ware, and it is not understood by those that try to spam blogs.