USB ports don't work. Or do they?

I have a problem with my Macbook (early 2008). It suddenly stopped recognizing some USB devices.

Here is the list of devices I tried to connect to the Macbook. YES/NO at the device name means whether it works or not:

- my iPhone 3G - NO
- my girlfriend's iPod Nano - NO
- my external hard drive (WD My Book Essential 2.0) - YES
- friend's external hard drive (WD My Passport Essential) - NO
- friend's Nokia 5310 - NO
- both my USB Flash Drives - YES
- my Microsoft Habu Mouse - YES
- my Olympus digital camera - YES

I looked in System Profiler if the non-working devices are shown there but they are not. Any suggestions what might be the problem ?

Note: MacBook is fully charged and I've tried both my USB ports.