orkul-muv is a utility that assists in renaming a large number of Oracle datafiles (9i/10g) in bulk. For example, you create 20 tablespaces with 100 datafiles at /opt/oracle/oradata/instance/ by accident and these should go to /oradata1/instance/. This tool helps script out the following tasks: Taking tablespaces offline, renaming datafiles (in Oracle), copying datafiles (on filesystem), bringing tablespaces back online. It's really not much more than an intelligent parser that generates useful output you can copy and paste onto your system.
Please contact me for a copy of the beta release of the software. I am porting the code to Java. Chances are it won't be useful to you unless you came to this page looking specifically for a tool of this type.