While my site focuses on Internet marketing, I have a keen sympathy for the needs of small businesses and website developers. Let me share two tools I've found helpful:
Article Manager from interactivetools.com is a modestly-priced content manager, written in Perl, which produces static HTML webpages with short URLs -- important for search engine optimization. It contains a WYSIWYG editor so non-technical people can update their webpages easily and visually. It's especially useful for organizations where each department wants access to its own webpages -- but you don't want them to ruin the templates. To accomplish this it includes various levels of password authority, with accessible directories assigned to each user. I use this for part of my Web Marketing Today site, and have installed copies for a denominational organization and a church. It takes many hours to get the templates exactly right -- like any design. But once that's done the program works flawlessly. If you're a web designer, here's a tool you'll enjoy using for your clients' sites. Here's a longer review of this tool.
Master Syndicator from William Botranger allows you to give out a couple lines of JavaScript that other webmasters can paste on their site. These then pull content from your site, so you control the file and can update it when needed.