See your house biodegrade. "Your House Without You" is a quick, two-minute animation that shows you how long it would take your house to disintegrate, leaving no trace of your having lived in it. How long do you think it would take your ceiling to cave in? For your water pipes to corrode? Take your best guess then watch the animation — which is part of the promotion for Alan Weisman's book "The World Without Us" — to see how close you were. Afterward, you'll think differently about the structures we take for granted and the objects we think we own.

Watch a timelapse of the Earth warm up. British environmental and meteorological people used Google Earth to create "Climate Change In Our World," an "interactive animation showing how climate change and global temperature rises could affect our world over the next 100 years." With the app, you can see a visualization of global warming that will hopefully spur you into taking action to prepare for what's to come. The app also lets you zoom in to different cities to read geographic-specific tidbits of climate predictions.

Plant a tree — and register it online! The U.N. Environment Programme (UNEP) raised its tree planting goal to 7 billion trees by late 2009, up from the previous goal of 1 billion trees in 2007. Want your tree to be counted? All you have to do is fill out an online form to make your tree one of the 7 billion strong. The UNEP won't knock on your door to make sure your tree's standing tall, so it's up to you to make sure your tree gets the love it needs to survive.

^{Top photo credit: Kenn Brown}