Portable Guitar Tablature Editor? (GuitarPro, PowerTab, etc..)

Well, my second post here
Another great progam for musicians like me would be some kind of tablature editor, there are many like Guitar Pro but i doubt they are open source. But good news, there is a GuitarPro alike which is called TuxGuitar, it's open source and there are diferent ports for almost any system. That would be a great program to have