My freely available and improved Swedish Keyboard layout has now been updated to support 64-bit versions of Windows. You can find out more about the freeware product here.
For the last ten years I have neither used the native Swedish keyboard layout, nor the standard US keyboard layout. Instead, I have been a happy user of my own design: US with Swedish characters. It allows me to use the benefits of the US keyboard layout in combination with quick and unobtrusive access to the additional Swedish letters (å, ä and ö).