Despite our initial scepticism, there are some pretty compelling features in Mac OS X Lion. That said, it's still a beta and running it as your primary OS is a little risky for several reasons. If you want to give it a shot without the risk, you don't have to give up your current OS X installation or even boot from an external drive. Here's how.

Windows only: vSubst lets you assign drive letters to any local folder on your computer, letting you turn it into a virtual drive. It's a good way to organise files or simulate environments.

PC World was, like us, slightly amazed at how long a Windows 7 upgrade can take on a Vista system crammed with data. They recommend a good overall geek tip as a fix: creating a separate "data" partition.