If you plan on going to the 2008 Olympic Games in Beijing next summer, or you want to curse out the people who put dangerous chemicals in your toothpaste, you may want to learn Mandarin. For those non-linguists out there, Mandarin is a group of closely related Chinese dialects that are spoken in most of China.
Fluenz is a company that provides interactive language learning software that utilizes video and sound, not just text. Lessons can be downloaded onto your Windows Mobile smartphone so that you can study anywhere you have some downtime. The Fluenz Web site even provides a free demo if you are interested in learning the language of the Dragon State.