A greek fork of RazorLame front-end for use with LAME, a great MP3-Encoder: it’s very fast, it produces high-quality files, has many advanced features (like Variable Bitrates and Joint-Stereo), and it’s open source. Also mentioned at Holger Dors (RazorLame autor) page.
There’s no need for external software. LAME Encoder also included in the setup program