ecto, for a while, has had the ability to add Technorati tags to posts. This results in a chunk of html being added to the posts, within the <!-- technorati tags start --> <!-- technorati tags end --> tags.
This worked fine for me for a while, as the tags got added to the end of the post. But things didn't work right when I switched to posting with the MovableType api. ecto adds the tags at the end of the first part of the post, before the text in the mt_text_more field. This causes the tag to appear on the bottom when displayed on the main page, but smack in the middle of the post, when the whole post is displayed.
This made me think that technorati tags shouldn't be treated as part of the post text, but really meta data about the post. Then when displaying the post, a decision can be made on how and where to display the tags.
The technorati plugin for LifeType handles this pretty well. It adds a custom field where you can add the tags that will be associated with the post. The only problem about this is that you have to use the web interface to add the tags.