1.Arscod Social Slider
Description: The best Social Slider plugin for WordPress on the market. Easy to install, 3 click configuration, awesome tabs design. Easy way to get more shares, more traffic, more fans and popularity. Support for: Facebook steam & faces, Twitter, Google+, YouTube (Video stream: uploads, favorites, playlist, Vimeo (Video stream: my videos (uploaded videos only), my channels, my albums), LinkedIn, Pinterest.
Demo: http://www.howtowordpresstrainingvideos.com/social-slider-by-arscode-plugin-for-wordpress-fb-twitter-g-yt-linkedin-vimeo-pinterest/
2.Wp Estimation Payment Forms Builder
Description: Create easily your own flat and responsive cost estimation or payment forms on your wordpress website. This can be used to sell any type of service or products: applications, websites, graphics, pets, lunar fragments …. or anything else.
Demo: https://www.youtube.com/watch?v=OtpvjM7vJ4M
3.Digg-Digg
Description: With Digg Digg by Buffer, you have an all in one social sharing plugin for your blog. Display all social sharing buttons nicely on your blog and make it look amazing, just like Mashable.
Demo: https://www.youtube.com/watch?v=27Zu8qtT3GM
4.Easing Slider
Desciption: Create a slider in less than a minute. Easing Slider is an easy to use slider plugin for WordPress. Built for everyone, with over 500,000 downloads, it makes creating the perfect slider quick & easy. No coding required.
Demo: http://easingslider.com/
5.Gravity Forms v1.6.4.5.4
Description: Build and publish your WordPress forms in just minutes. No drudgery, just quick and easy form-building. Select your fields, configure your options and easily embed forms on your WordPress powered site using the built-in tools. That’s way more satisfying (and less fattening) than a peanutty candy bar any day.
Demo: http://demo.gravityforms.com/
6.Machform
Description: MachForm is an excellent, easy to use form builder that you host on your own server or site. Until now, its been difficult and required “jumping through some hoops” to embed a form made with MachForm on your WordPress site. That is no more! You can now add a MachForm form anywhere on your site using a simple shortcode! Need a form in a blog post? Need a form on a page? No problem.
Demo: http://www.appnitro.com/demo/manage_forms.php
7.OptinSkin
Description: Various opt in forms, clean design, easy to use, great tracking features and fade in option to draw attention to your opt ins.
Demo: http://optinskin.com/
8.Popup Domination v3
Description: The Best Way To Get Email Subscribers.It gets us more subscribers than homepage opt-in, sidebar op-tin, footer opt-in and squeeze pages combined.
Demo: http://www.popupdomination.com/demo/
9.Woocommerce Product Addons
Description: Allow your customers to customize your products by adding new options such as input boxes, dropdowns or checkboxes. With the Product Add-Ons extension, gift messages, donations, laser engraving and any other product that requires user input is now an option for your customers!
Demo: https://bobwp.com/create-add-ons-for-your-woocommerce-products-easily/