Commercial

Kayako นิยมมาก มีทั้งระบบ helpdesk (eSupport) และ live chat (LiveResponse) ดูราคาที่นี่

Cerberus Helpdesk นี่ก็นิยมไม่แพ้กัน ลองดูตัวอย่างหน้าจอและ feature

Inverseflow มี product แยกขาย ทั้งที่่เป็น helpdesk, live supoprt และอื่นๆ

phplive อันนี้เป็น live support อย่างเดียว และก็ทำได้ดีด้วย

HelpOnClick

liveperson

websitealive

LiveHelp จาก stardevelop อันนี้ก็นิยมเหมือนกันครับ
<div class="quotetop">QUOTE</div><div class="quotemain"> Live Help Messenger is a customer service software solution that allows customer support operators to chat with your web site visitors and potential customers. Live Support enables you to instantly add PHP Live Help Customer Support Software to your web site to increase your sales and customer satisfaction. </div>

SupportTrio จาก activecampaign

livechatnow

LiveDesk Pro

Opensource

OTRS (Open source Ticket Request System)
<div class="quotetop">
</div><blockquote><div class="quotemain"> OTRS is an Open source Ticket Request System (also well known as trouble ticket system) with many features to manage customer telephone calls and e-mails. The system is built to allow your support, sales, pre-sales, billing, internal IT, helpdesk, etc. department to react quickly to inbound inquiries. Do you receive many e-mails and want to answer them with a team of agents? You’re going to love the OTRS! </div></blockquote>

RT (Request Tracker)
<blockquote><div class="quotemain"> RT is an enterprise-grade ticketing system which enables a group of people to intelligently and efficiently manage tasks, issues, and requests submitted by a community of users. [more] </div></blockquote>
craftysyntax
<blockquote><div class="quotemain"> Crafty Syntax Live Help (CSLH) is an open source live support solution that helps customer support with live help functionality that can be proactively pushed to visitors to your site or requested by the consumer. Crafty Syntax includes a large range of features to allow multiple operators, multiple departments and multiple languages to be used…</div></blockquote>