After using VirtualBox (version 3.0.12) for 3 months now, I've made some notes on things that fall into the 'good to know' category to make virtual computing easier.

1) Don't burn a CD for each operating system, the raw ISO file on your hard drive is just fine.
2) Installing guest additions makes the virtual machine's interface more responsive.
3) Setting up permanent shared folders makes working with files from one machine to another simple.
4) Backing up machines is as easy as copying the .VDI file.
5) Cloning a virtual machine to another physical machine is an easy way to copy your computing environment from a desktop to a laptop.

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