My iPhone 3G is acting funny, and not in the Jerry Seinfeld kind of way. Every time I run my finger near the bottom left of the screen the liquid in the crystal display moves around creating those rainbow colour effects that you get when you press really hard on a display (esp. calculators, for those who don't understand what I'm trying to explain). I'm not pressing hard with the intention of creating them - I'm merely tapping and touching. It's really obvious when the screen is a solid colour and it's starting to annoy me. It's only happening in that area and I just noticed it the other day. Is this a somewhat common issue with a certain number of iPhone 3Gs, or am I the only one at this party? I can't decide if I should bother taking it to the Apple store or if they'll just tell me that it's fine. I'm worried that it's a sign my screen is weakening in that area, and that it's going to break or crack at some point. Suggestions/comments/concerns/impersonations?