To attract small businesses to its new software, tech company Atlassian knew it had to offer something more intriguing than a free trial. Instead it gave very small firms use of the product for $10 and promised to donate that money to a global literacy charity -- inspiring many mentions on Facebook and Twitter. Since making the offer in 2009, it has raised $1.5 million for the charity, Room to Read. And it's sold about $8 million in products to customers trading up from the $10 package.
NEXT: 2. Offbeat invites
