Shashin 1.0 is now available. New features include an options menu (so you don’t have to touch the code to change settings), improved random image and thumbnail display features, the ability to show the latest uploads to your albums, and UTF-8 support. Thanks to everyone who helped with the beta testing (the beta version was downloaded exactly 100 times).
Shashin is available at the WordPress plugin repository now, so you can get it there as well. The plugin repository requires a readme.txt file with an FAQ section. To avoid maintaining two sets of documentation, I rewrote my Shashin page to also follow the FAQ format.
If you’re crazy for code, you can read the PHPDoc documentation.