Computer Backgrounds at any DPI!
Perhaps I am the only one not knowing this, but I was amazed to learn that you can set a graphic to whatever DPI you want and it still displays sharp on your monitor. That is, you can make an image 1600X1200 with a DPI of 2 (yes, 2!) and set it to your desktop background. It displays beautifully. This, in my opinion, is a huge deal to anyone wishing to make images for other people, or even yourself. Apparently it does not decrease the file size (for whatever reason). You can create lovely images that ought not print well, so you do not need to worry about others lifting your work. Give it a shot.