Google.com/sky lets you explore the far reaches of the universe using images from NASA satellite, the Sloan Digital Sky Survey, and the Hubble Telescope.
Google Books nGram Viewer is a fun tool that lets you search for words in 5.2 million books published between 1500 and 2008 so you can see how they've been used and changed over time.
You can even plot how different search terms have waxed or waned over time.
Google Express lets you get same-day delivery for food, electronics, books, and more. The service now covers about 90% of the United States.
The Google Sound Search widget works like Shazam to help you identify songs you hear. It will also link you to buy each track in the Google Play Store.
Google has a catalog of animal noises that you can easily find by typing in "animal sounds" or by typing in the name of a specific animal. Hot tip: Whip this one out while babysitting and it'll keep kids entertained for a long time.
Gboard is an app for iPhone that enables Google search right in your keyboard, eliminating the need to hop back and forth between apps.
If you can't decide between causes to donate to, or have trouble finding a reputable charity, Google's One Today app makes it easy. The app shows different charities, gives a short description, and lets you know how you can help.