There are many multiple file rename utilities that you can dig up.
One that I am used to on Debian/Ubuntu-based distros is called rename which is one that is derived from the Perl Cookbook. However, note that this rename script does not seem to exist on other UNIX variants in a packaged format. It definitely does not seem to exist on a Fedora Core 9 box I use nor does it exist on a FreeBSD machine.
While it would not be too hard to swipe the perl script and copy it in place onto a system. I hate having to remember moving that script around and around with me from place to place so I looked around for other equivalents and found one called mmv. One nice thing is that there are packages for at least FreeBSD, FC9, and Debian/Ubuntu variants so it should be quite lazy to install compared to rename.
Below I give an example of using it to do a multiple renaming where I want to append the value 1 to the end of a bunch of filenames.
$ ls cat_100 cat_15 cat_200 cat_50 cat_500
$ mmv cat"*" cat#1_1 $ ls cat_100_1 cat_15_1 cat_200_1 cat_500_1 cat_50_1
