About the software
Tabber is a guitar tablature editor for Windows. The program is free and open-source. It uses plain text files to store tablatures, similar to the ones you can find on the Online Guitar Archive.
The idea behind Tabber is that, in author's opinion, the most convenient tool to edit guitar tablatures is Windows' notepad. However, notepad lacks a few functionalities such as staff insertion, predefined chords and so on. Tabber's modest aim is to bring these few functionalities into a classic text editor.
See this page for complete feature list.
Tabber is now available in its 2.0 version (refer to the download section).
Tabber 1.0 users (this version can be found here) are encouraged to upgrade their software, as most of the problems of the first version have been solved in this release.