Zendesk - Zendesk is a beautiful, lightweight help-desk solution.
TeamViewer - TeamViewer lets you establish a connection to any PC or server within just a few seconds.
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
LogMeIn - LogMeIn gives you fast, easy remote access to your PC or Mac from your browser, desktop and mobile...
HelpScout - Help Scout is a simple, straightforward way to provide excellent support
UltraVNC - VNC remote access software, support server and viewer software for on demand remote computer support. Remote desktop support software for remote PC control. Free