Added "Previous Discussion" links in right column.
Any other suggestions for improving navigation and site coherence are welcomed in Comments to this post. (Bearing in mind, of course, that 1) Blogger is not the world's most sophisticated site-design tool, and is quite insular about what improvements it's prepared to support; and 2) Your Hosts are a smidge code-shy, and unless you're prepared to write and debug the code yourself, don't go suggesting hyper-advanced functionality...)
In other news, the Technorati Search widget now appears to be working as designed. Give it a try!