Memrise is an online farming game similar to Viva Pinata. It's built on words, not some silly buzzlegums and mixes addictive gaming with mnemonics to make learning a new language fun.
The concept is brilliant but so obvious you'll kick yourself for not thinking of it first. Each foreign word you learn is planted in your garden. The more words you learn, the more beautiful your garden will be.
Here's the kicker. You have to keep using these words if you want your garden to grow. Neglect your words and your garden will wither and die.
Languages are restricted to English or Mandarin Chinese, but other languages will be coming soon. It's a great idea for a web app, but imagine what would happen if it was ported to Facebook. Yowsers. [Technology Review; Shutterstock/BestPhoto1]