UserAgent Theme Switcher is a simple plugin that lets you change the theme to be displayed according to the detected browser. It checks from a predefined list useragent so that the user can at will change the theme shown for that browser. For example, a user can configure a special theme for mobile phones that is lighter and thus adapted to these devices. It is ideal for displaying themes ready for Opera Mobile, Internet Explorer Mobile, iPhone, Android, etc.
WordPress FAQ is a cool plugin for creating your FAQ section . It has a lot of parameters to set, and it will allow you set your own theme from scratch. It has a user-friendly front-end and back-end interface, allowing you to set all parameters quickly and easily. FAQs have SEO-friendly URLs.
Joomla contact form builder extension is a complicated tool for making submission forms for your Joomla website. It permits you to specify parameters like colors and fonts. It can use a Google map when given an address or geographical coordinates (longitude and latitude), and the user can drag the marker to the required location.