Why do you want to load a 4+ GB file into memory? Even if you find a text editor that can do that, does your machine have 4 GB of memory? And unless it has a lot more than 4 GB in physical memory, your machine will slow down a lot and go swap file crazy.
So why do you want a 4+ GB file? If you want to transform it, or do a search and replace, you may be better off writing a small quick program to do it.
