To quickly mute the volume of any application, simply hold the volume rocker down for a few seconds and the volume will be muted.
You can cut precious time by letting Safari auto-complete web forms. Simply go to Settings>Safari>AutoFill and then select Use Contact Info to autofill information from the Contact app.
If your device freezes or something isn't working right, the quickest way to fix it is to do a soft reset. Just hold the power (top) and home (bottom) button together for a few seconds and everything will be good as new.
Import your own eBooks
Besides buying books from the app store you can also download free eBooks in the ePub format that iBooks supports. Sites like Project Gutenberg offer around 30,000 free ePub books that you can download.
Use it as a Digital photo frame
When you're not using the iPad for surfing or work, it can also double up as a photoframe. When you hit the wake button, don't slide to unlock it. On the right you'll see a little flower icon, press it and the slideshow will begin. You can toggle the speed of the transitions in the Settings menu.