9. Crosswords

Free Crosswords @ Bestcrosswords.com

Rather than buying a book of puzzles to kill your time in a three-hour flight, you can choose from a wide range of free printable crosswords as its solutions as well. You can also save them on your computer to play them later. A puzzle book will finish after 200 puzzles but the free stock here is endless.

10. Greeting Card

Free Greeting Card @ 123greetings.com

You can always send a wish with a few clicks by 123greetings.com. Such greetings websites save you penny which you might have wasted on a paper card and its postage. There are online cards which are animated and musical as well. You can always set the date and time in advance, that at which the card to be sent.