I added a couple of new features over the last few days.
First, I discovered why the Related Posts plugin wasn’t giving very useful results: it was doing a search based on the title of the current post, which is great if you always use descriptive titles. The problem is, we don’t. (“Quick Turnover,” for instance, was getting associated with recipes instead of Linux!) So I fiddled around with it a bit to get it to use the post excerpt or the first 50 words of the post instead, which results in a much more relevant list. (I’ll post the code at some point once I’ve figured out what the etiquette is for releasing modified plugins)
Unfortunately, adding the extra search terms really slows it down. Between that and Waypath, it would sometimes take several seconds just to generate a page. So I disabled compression and turned on the Staticize plugin, which massively improved speed (except for the first time someone looks at a page), but of course had a cost in bandwidth.
Solution: install mod_gzip server-wide. It enables compression for every website on the server, improving performance for everyone! (Yaay!)