EmEditor ( http://www.emeditor.com/ http://www.emeditor.com/ ) handles large files very nicely. It has a special 'large file controller' that lets you configure

EmEditor ( http://www.emeditor.com/ http://www.emeditor.com/ ) handles large files very nicely. It has a special 'large file controller' that lets you configure in real-time how to access a file. I've edited 4GB text files (global search & replace) and the only slow step is the final 'save' function.