Firefox 2 got a Storage – database API baked by sqlite. It makes possible to operate any sqlite database from firefox programmatically. And finally someone created most exotic desktop SQLite Manager – XUL application, running in Firefox or XULRunner, needless to say it is crossplatform. Not that much features in current state (0.1.x), but does it really matter).
The pics:

SQLite Manager v.0.1.7 on Windows

SQLite Manager v.0.1.7 on Linux Fedora Core 4

Downloads etc