Apple has released Thunderbolt Firmware Update v1.2 to address stability issues with using Target Disk Mode (which makes one Mac appear as a hard drive to another Thunderbolt-connected Mac). The update is for only those Macs with a Thunderbolt port, and it requires OS X 10.8.3 Mountain Lion or later. As always with firmware updates, although you can download it manually, we recommend relying on Software Update or the App Store app to ensure you get the right firmware update for your Thunderbolt-equipped Mac, and be sure not to interrupt the update process. (Free, 1.22 MB)
Open a Finder Window with the App Switcher
If you don't have any Finder windows open and want to switch to the Finder and open a window in one fell swoop, bring up the app switcher with Command-Tab and tab over to the Finder icon. While still holding down Command, press the Option key, and then release the Command key. You're switched to the Finder, with a new default window open for you.