I've started to use labels for my posts. I have also retrolabelled some posts, which I will probably continue to do--ah, like so much else in my life--sporadically and incompletely. Whether going back or going forward, I am not going to go labelloony, either in giving many labels to individual posts or thinking that a post is naked if there isn't some label stuck to it.
I don't know if it is possible to include labels in my sidebar without having to entirely overhaul my template to the new style Blogger uses. If it is and I figure it out, I'll include them in my sidebar, as I know people are eager to be able to spend hours going back and re-reading all of my posts about karaoke or my short short fiction writing.