Merkaartor is another desktop editing application, this one written in C++ and available for Windows, several versions of Linux, and a pre-release version for Mac OS X. It's a native application, which means you need to install it before you can use it, but it can be used for offline mapping.
Merkaartor is much closer in appearance and use to a traditional GIS system than the other OpenStreetMap editors. It has a high-quality rendering, multiple layers, sophisticated management of map changes, and drawing tools. However, it's not extensible in the same way as JOSM, and some features such as audio mapping aren't included. Along with editing data, you can use Merkaartor to render maps, including customizing the style.
You can download the latest version of Merkaartor from http://merkaartor.be/, where you'll also find installation instructions for your platform. The other documentation for Merkaartor is kept in the OpenStreetMap wiki at http://wiki.openstreetmap.org/wiki/Merkaartor...