hi, i have an issue that i haven't been able to find sufficient explanation for. the other day i noticed a faint vertical line of pixels on the far left of my screen. they weren't black or colored, just faint/dim. i tried switching my desktop background, and the line was still there. i restarted my computer, and the line was still there. i shut down the computer, thinking that i would find the line there in the morning and have to take it to the apple store. when i turned the computer on the next morning, there was no line. however, later that evening i noticed a reappearance of the line. i restarted the computer and left for a while. when i came back later, i woke the computer from sleep mode, and the line was gone. there was no line on the computer this morning, although after a couple hours of use, i noticed that two lines had developed on the edge of where i had application windows open -- in this case, both yahoo messenger for mac. curiously, this didn't happen with other windows (finder, safari, etc). anyone have any ideas? is this an issue with my display? graphics card? yahoo messenger? thanks!