Crazy Clie refused to recognize the Memory stick

Something funky happened to my PDA Clie while I was using it on MTR (it's a underground railway, for those who are in living in Hong Kong). The PDA failed to recognize the existence of the memory stick, and gave me a "memory card not exist" icon at the bottom of the screen. No matter how many times I ejected and reinserted the memory stick, the system still didn't see it. By that time I already arrive the dance studio for a dance class, so I left the PDA alone.

And now that I am home now, I take out the PDA and found that the PDA can recognize the Memory stick again! But the strange thing is that the battery indicator shows that there's only half the battery left. This does not making sense since I only used the PDA for less than 15 minutes before my last charge.

So here you go. Another Hi-Tech mystery. Once again proving that technology is like 3 steps forward 2 steps back. Well, at least we move one step forward.