Here is Android x86, an open source project which allows you to put Google's Android OS on PC hardware. While there is some software that won't work, it's surprisingly capable! While obviously best for netbooks it's capable of running on many laptops, or you could consider running it in a virtual machine if you just want to run Android software on your PC for a bit. Here's the download page (the proper boot media can be found under "Android-x86-4.4") and installation instructions.
Here is Incursion: Halls of the Goblin King, a computer game that adapts the 3rd Edition rules of the Dungeons & Dragons game to roguelikes.
Here are some free tools for rescuing infected Windows systems: Windows Defender Offline Beta - Kaspersky Rescue Disk 10 - BitDefender Bootable CD - Avira Bootable CD - How To Geek provides instructions for scanning a system from an Ubuntu Live CD. For more info, click through.... [more inside]