It would be just plain wrong for me to forward mail to anyone I didn't have a clear and narrowly-defined "understanding" with about what would be acceptable. Forwarded mail is close relative to the chain-letter family.
I often do, however, include (very small) cut-and-paste snippets, and links to specific web pages, but always with a brief and accurate description. ("Guess What?" and "Look Here" and other cheap mousetrap sucker CHEESE bait tactics is just plain evil.)
I have also linked to a few different donationcoder projects in my posts in software forums.
If you build it, they will come.