I created these photo galleries with this ingenious Perl script licensed under the GPL. It's very small, have a play, tell me what you think, send me patches. If it becomes popular, these pages will expand. You'll need a Unix system with Perl and the netpbm tools; also, it helps if you can hack Perl.
I'm constantly hacking on this script as my needs expand, so the version here will be out of date; if it doesn't do what you want, ask me for the latest version.
I love being mailed questions, please don't hesitate to get in touch.