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.
Canonical's Ubuntu for Android offers a full Ubuntu Linux distribution running on a dual core Android smartphone when placed in a docking station. (photos) [more inside]
The U.S. National Security Agency (NSA) has begun releasing Security-Enhanced Android patches and tools, which port their Security-Enhanced Linux tools to Android devices. SEAndroid and SELinux provide mandatory access control designed to limit the amount of damage that rogue or exploited software can do. [more inside]
Why Is Microsoft Seeking New State Laws That Allow it to Sue Competitors For Piracy by Overseas Suppliers?
Nokia has announced the n900 running the maemo Linux based operating system will be released in October. The phone has similar specifications to the iphone, but with a keyboard and considerably higher resolution display (800x480). In addition the OS is an open platform with free GPL development tools. More from The Guardian and CNET.