Learning about forex is very interesting... I agree with what you guys say.
Let me share with you something called Big Mac Index. Yup, the McDonald's Big Mac. You see different countries price Big Mac differently. Ideally all Big Macs should be priced the same. For example, if Big Mac is USD1 in US, Malaysia's should be RM3.50. Of course, this is not happening.
So, from there, the difference can signal whether a currency is undervalued or overvalued to cut the topic short
Here's the link: http://www.economist.com/markets/indicators/displaystory.cfm?story_id=8649005