Google has the world's most advanced Cloud Computing infrastructure. The best technologies stay out of the way and disappear into the background. The Google.com search engine is the world's most popular software-as-a-service application. Of course it can search, but it can do much more.
Google.com is a calculator.
Just enter your math problem into the search or omnibar and Google will give you your answer.
Google.com is unit converter.
Dollars to Euros? Inches to centimeters. Pounds to onces? Megabytes to gigabytes? And much more.
Google.com can check your flight status.
Enter your flight number into the Google.com search engine to learn the status of your flight as well as terminal and gate information.
Google will tell you the current time anywhere in the world.
Just ask Google, "What time is it ..." and the search engine is happy to let you know.
Search with your voice.
Google's voice recognition software is some of the best in the business and improving rapidly. You can search with your voice on any device or PC.
Search with images.
Can't remember the name of a landmark or building you captured in a picture? Try going to images.google.com and uploading the image. Google may know exactly what it's called. Google also has some of the world's best image recognition software. They're making extensive use of these capabilities in Google+, allowing you to search your pictures for people, pets, places, buildings, landmarks, characteristics, etc.
My personal favorite is the calculator, I use it constantly. Flight search has saved me a few times as well. What's your favorite?