Good free Helpdesk software? [closed]

looking for good free or open-source Help Desk software.

And by Help Desk Software I don't mean development issue tracking (which is slightly different), I mean software that is optimised towards tracking support requests from the user base of a small-medium business. So something like ZenDesk, rather than something like JIRA.

Particularly interested in solutions that also integrate asset tracking.

I'm aware that there's a big list at http://www.opensourcehelpdesklist.com, but I'm hoping to hear from people who actually have evaluated some of these solutions.

(While I did find a few similar questions on StackOverflow, the answers tended towards issue tracking systems rather than helpdesk systems, which is why I'm asking this question again)

I use OTRS (http://otrs.org) for my "support desk" functionality. It is a very powerful application and does a nice job. I will admit that it is a little daunting at first (initial configuration, etc.), but once you get going, you'll be quite impressed.

My customers can send an email to the support address and OTRS will, based on my rules, funnel tickets into the correct queues. It also will send them email updates as the ticket status changes. It also has a customer facing web interface that is easily skinned.

And if you are so inclined, they are moving the product to be ITIL compliant.

Best Practical: Request Tracker

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.

RT manages key tasks such as the identification, prioritization, assignment, resolution and notification required by enterprise-critical applications including project management, help desk, NOC ticketing, CRM and software development.

RT is used by Fortune 100 companies, government agencies, educational institutions, and development organizations worldwide.