Windows 10 Technical Preview Now Available
Microsoft took the wraps off Windows 10 yesterday (we've got nine things you should know about it), and today it has released the technical preview version, allowing anyone interested to download it and give it a go. Both x64 and x86 ISOs are available to download.
Of course, if you do choose to download and install, it is important to keep in mind that this is a technical preview, and so you should take the precautions necessary: back up all your data all the time, and expect that you'll run into problems, including issues getting hardware to work, system crashes, and trouble installing some things.
Microsoft has taken some big steps to make sure you know what you're getting into, tossing up a "Before you install" page related to the technical preview, as well as some details on the system requirements and other pertinent information.
If you decide to go ahead with giving the technical preview a try, you can check out a how-to video here with a run down of different tips and changes. You can grab the ISO for your machine in your preferred language over at the Windows Insider Program page, where there are included instructions to help get you started.