Sium

This is a very simple alternative to attachment mod. 
It works only with images and allows users to quickly add images to posts. 
All images are stored on third party image hosting service and bbcode for 
images is automatically inserted in posts when users upload images. 
Thumbnails are automatically created on image hosting server. 
This mod is very easy to install and very easy to use.
Other options and language settings are available here: <a href="http://postimage.org/mod.php" rel="nofollow ugc">http://postimage.org/mod.php</a>
Powered by <a href="http://postimage.org/" rel="nofollow ugc">Postimage.org</a>

Simple Image Upload

This mod integrates image hosting with WordPress

Global Programming

The WHMCS Bridge plugin integrates your WHMCS support and billing software into WordPress providing a seamless and consistent user experience to your customers.
Thanks to the theme inheritance feature, you don’t need to style your WHMCS installation anymore, the integration ensures that your WHMCS installation looks and feels like your WordPress site.
Full installation video (incl. Pro, SSL, WHMCS addon and caching) 
<iframe loading="lazy" class="youtube-player" width="750" height="422" src="https://www.youtube.com/embed/gRxXTDPVkV0?version=3&rel=1&showsearch=0&showinfo=1&iv_load_policy=1&fs=1&hl=en-US&autohide=2&wmode=transparent" allowfullscreen="true" style="border:0;" sandbox="allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox"></iframe>
Our Pro version additionally offers:
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Caching: Supercharge your bridge with caching up to 30 days all parsed CSS and JS files to speed up loading time and reduce resource usage.
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Support for WHMCS MarketConnect: Full support for WHMCS MarketConnect allowing you to quickly and seamlessly re-sell products via WHMCS (via WordPress) using WHMCS MarketPlace.
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Support for Sign-in Integrationss: Upgrade and support Google oAuth and Facebook Login (Twitter not supported)
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Support for WHMCS Friendly URLs: Upgrade and support WHMCS “Full Friendly Rewrite” instead of “Basic URLs”
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Pretty permalinks: display links like http://www.mysite.tld/clientarea/ rather than http://www.mysite.tld/?ccce=clientarea. Also supports knowledgebase, announcement and download links.
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SEO Titles: Each Bridge page has it’s correct title tag from your WHMCS installation.
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Custom Templates: Use any template you like, including custom templates.
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Enhanced visual integration: using cross-domain messaging for a smoother visual integration
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Single sign on: thanks to the single sign-on feature, your customers can sign in once on your site and comment on your blog postings, share information with their peers, order hosting plans and pay their bills.
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Multi-lingual WHMCS support: fully integrated with qtranslate & WPML
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IP address resolution ‘patch’: shows your customer’s IP address instead of your server’s IP address during sign up
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Choose your WHMCS portal:fully compatible with the WHMCS ‘six’ responsive template
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Shortcodes: use WordPress shortcodes on your pages to integrate WHMCS pages
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Thanks to the single sign-on feature (WHMCS Bridge Pro plugin), your customers can sign in once on your site and comment on your blog postings, share information with their peers, order hosting plans and pay their bills.

WHMCS Bridge

WHMCS Bridge is a plugin that integrates the powerful WHMCS support and billing software with WordPress.

Simple Image Upload vs WHMCS Bridge