For some reason, I've got some graphical issues sometimes. Mostly with AbiWord, LibreOffice (and OpenOffice.org), and Wine applications. I've added some screenshots below t oclarify a bit.
This is not a problem that recently popped up. As a matter of fact, I've always had it since Ubuntu 8.10, and there never came an update to fix it. I'm currently using Linux Mint 10 (based upon Ubuntu 10.10), but as I already said, that doesn't really say much as I'va also had this problem with Linux Mint 8, Ubuntu 8.10, Ubuntu 9.04, Ubuntu 9.10 and Ubuntu 10.04. It was never a big problem, as I rarely used any text processing programs. But recently, I'm starting to use them more and more, and it's really annoying being unable to work because of this problem. When I first open an application, everything looks normal, then after a while (when I highlight, click, ... an item) they'll suddenly screw up. This also happens when I move or resize the window. Sometimes when this happens, I can just minimize the window, and when i restore it, sometimes it will be gone (for a few seconds at least) or it will have changed positions.
I'm using the nvidia-current graphics card driver. But I have also always had this problem on my old computer, wich used... I think nvidia-96.
(I've done the blur myself, so that's not the issue, the problem is that blue crap)