Just recently I have been doing a lot of work on setting up and upgrading our internal and external networks. It has been quite an interesting and challenging job, that I am only just starting to get to grips with and I have learnt a lot about how to setup networks using open source software.
VirtualBox is brilliant (and Open Source) Virtualization software, produced by Sun. I use VirtualBox regularly to test out systems, different operating systems or web sites and applications in different browsers and environments. Whenever I use it however I always seem to forget this one step, so it is worth noting it down.