CardDavMATE is a CardDAV Web client with a powerful vCard editor. It is compatible with Safari/Mobile Safari, Webkit, Epiphany, iCab, Chrome, Firefox, and IE9, and supports all major CardDAV servers.
CalDavZAP is a CalDAV Web client with a powerful event/todo editor. It is compatible with Safari, Webkit, Firefox, Opera (15+), iCab, and Chrome, and supports all major CalDAV servers.
QStode is a Web application which allows registered users to store bookmarks (like the old del.icio.us) categorized by tags.
An easy database query library.
An autodiscovering network observation system.