Whatsim
Whatsim Card is an ingenious idea, what it does is quite amazing, it´s the world´s first card that lets you chat around the world. For only $10 you can buy about 50 Mb, that translates in around 25.000 text messages! You can then top it up with some more credit, if you want to send some images, videos or voice messages. They cover the whole world so you´ll be always connected and able to update your status or just keep in touch with friends and loved ones. If you travel a lot this is just the thing to have to stay connected and not to worry about mobile operator coverage. Whatsim works in all unlocked phones, you can get it at their online store (here) and it won´t expire if you use it at least once every 12 months.