Web-based HelpDesk Software

I've been looking at using a helpdesk and ticketing system to help manage my ever growing task list. Email worked for a good while, but the the added step of putting it on the task list has caused some support issues to lose priority or fall through the cracks completely. With a helpdesk program, customers can log in to a web site and open a support ticket that gets added automatically to my list and keep them updated via email as to the progress.

Since the name of the game is "FREE", I've looked at osTicket, Support Logic, PHP Support Tickets, Crafty Syntax Live Help and Liberum. Liberum is my choice since it's very easy to setup, easy for a non-techie to open a ticket and has a very simple yet clean interface.