jQuery Plug-ins (Part 1)

Rcarousel: http://ryrych.github.io/rcarousel/
Development has been discontinued at the moment, nonetheless it is a highly customizable carousel with broad support for new and old browsers.

Complexify: http://danpalmer.me/jquery-complexify/
This will help you provide your users with feedback on how good their password is. Very easy to use!

Arctext: http://tympanus.net/Development/Arctext/
With little code, you can make your text curved, change its direction, animate it and more.

iCheck: http://fronteed.com/iCheck/
Unlimited options to customize checkboxes and radio buttons, and more important, identical results across browsers.

PickADate: http://amsul.ca/pickadate.js/
Lightweight date and timer input picker.