Medoo is a lightweight (~8kb) PHP framework for working with SQL databases. The framework comes as a single file and works withВ MySQL, MSSQL, PostgreSQL,В SQLite (and more).
In order to manage MongoDB databases easily, Genghis, a single-file, self-hosted and web-based solution is pretty handy. It can be installed either as a Ruby gem or as a standalone PHP script.
Maplace.js is a jQuery plugin that simplifies integrating Google Maps into websites. It works with the latest Google Maps API (v3) and has methods for adding markers + custom content and drawing paths, polygons or routes.
Spectrum is a jQuery colorpicker plugin that probably comes with all the features you are looking for. It is image-free (only CSS and JS) and can be used for all browsers or only as a polyfill for the input[type=color] of HTML5.
DeepTissue.js is a library that removes such differences (of MSPointer, WebKit Touch and mouse pointer APIs) and provides a cross-browser gesture handling library.
Typeahead.js for building smart auto-complete form fields comes as a jQuery plugin, shows suggestion as-users-type and can feature top suggestions with the help of styling.
iLightBox is a fresh alternative to other jQuery lightbox plugins and there is a strong chance that, although it is a paid resource,В it may become your favorite.