I just discovered that on the Linux system at work here has the "rename" command.
According to the manpage it's part of the "util-linux-ng" package.
Code:
RENAME(1) Linux Programmer’s Manual RENAME(1)
NAME
rename - Rename files
SYNOPSIS
rename from to file...
rename -V
DESCRIPTION
rename will rename the specified files by replacing the first occurrence of from in their name by to.
-V, --version
Display version information and exit.
For example, given the files
foo1, ..., foo9, foo10, ..., foo278, the commands
rename foo foo0 foo?
rename foo foo0 foo??
will turn them into foo001, ..., foo009, foo010, ..., foo278.
And
rename .htm .html *.htm
will fix the extension of your html files.
SEE ALSO
mmv(1), mv(1)
AVAILABILITY
The rename command is part of the util-linux-ng package and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux-
ng/.
1 January 2000 RENAME(1)
Seems to be installed by default on fedora core 11.
For example to replace all underscores with a plus:
$ rename '_' '+' *
One page I found on the internet (Which is about something different entirly and just mentions this command) used a regular expression, but that doesn't seem to work for me. Didn't research it.