mhWaveEdit is a graphical program for editing sound files.

Features
   - Loads, plays, records and saves wav-files and a few other formats as well.
   - If the file is small, it's loaded into memory. Otherwise, it's edited on
     disc.
   - Cut, copy and paste.
   - Zooming
   - Volume and speed adjustment
   - Convert between sample rates, sample sizes, stereo and mono
   - You can always undo, all the way back to the original state of the file
     (even when editing large files.)

WWW: http://gna.org/projects/mhwaveedit/