How do I take a screenshot on a Honeycomb tablet? Is there a built-in mechanism to take a screenshot on my Samsung Galaxy Tab 10.1?  Or is there an app I can download to do so (without rooting the device)?
Unfortunately, it does not appear that straight Honeycomb (Xoom, Samsung 10.1, etc) devices have the ability to take a screenshot without some help.  

If you have the SDK downloaded you are able to plugin your device and take screenshots using your computer.  However, that sounds really inconvenient. Instructions can be found here under "Debugging Tips" http://developer.android.com/guide/developing/debugging/index.html 

There was also an independent app released on XDA for Honeycomb devices called Screenshot ER.  One caveat, it does require root.  http://www.xda-developers.com/android/take-screenshots-of-your-honeycomb-device-with-screenshot-er/ 

Market link at https://market.android.com/details?id=fahrbot.apps.screen&amp;feature=search_result