I use TRAC to deal with tickets inside my company, few customizations on it (http://trac.edgewall.org/) to add an agenda and something more, I've disabled few parts of it (code tracking for example) but basically it works fine

Ben

HW Repairs it's a totally different story, if you need to deal with quotations, repair sheets, warranty and so on I've used a self made project built on top of Apache/PHP/MySQL; integrated with TRAC itself but it's a different software

Ben

I've used a LAMP solution in the company where I work because I'm confortable with it. With this web app I've solved these problems:
- multiplatform (Windows, Linux, OS-X)
- low level specs PCs (our tech lab)
- no sw installation or upgrades, they just need a browser to run everything
- multi site usage through VPN in our intranet

I've started with Drupal in the beginning but later on I've switched to a custom based solution because I'd like to have less dependencies as possible, in my case only: PHP5, MySQL, Apache, Kerberos and I'd like to manage each page or program in the way I want.

By the way if you don't wanna spend ages on development you may even take a look at few incoming solutions for hw centers, mostly CRM solutions with plugins or modules for hw centers, something like:

vtiger - http://vtiger.com/ a newcoming CRM with a lot of new ideas
myIT CRM - http://myitcrm.com/
and few more... but I guess other CRM have hw modules for companies like your

let me know what do you think about it
Ben