PrefixSuffix: Rename Multiple Files
PrefixSuffix is a simple Linux GUI application that renames multiple files. It pretty much does (only) what its name says, rename prefixes and suffixes.
If you want full-blown rename tool, check out KRename. The multi-renamer tool in GNOME Commander is also very advanced, with built-in support for EXIF, ID3, and other metadata standards.