I'm glad you're using the wonderful OS that is Ubuntu! Now, you may have come across a simple yet irritating problem when trying to play rm, rmvb or any other RealMedia files. Don't go running back to Windows just yet! There's a simple solution to that ;)

Steps:
1- Download the RealPlayer bin package.
Deb Package | Rpm Package
2- Double click the bin file and select install.
~May require downloading more files.
3- That's it! Enjoy watching ;)