My blog-friend Amy clued me in to this helpful hint last year...by changing this setting (see instructions below), when you leave a comment on someone's blog, the author can respond to you directly via email. It's especially helpful when you ask a question in your comment!
1~ Go to your Dashboard; click on "Edit Profile" (blue link on LH side)
2~ Click the box that says "Show my email address"
3~ Save your changes...and now I will be able to respond to your comments with a direct email!