If you hate the intrusive installation of Real Player, try Real Alternative; it will allow you to play RealMedia files without having to install RealPlayer. All RealMedia formats are supported (.ra .rm .rmvb .ram .rpm .rv .rp .rt .rnx .smi .smil etc.), including streaming content and RealMedia content that is embedded in webpages.
Features at a glance: Quick and easy install; Proper uninstallation; No background processes; Low on resources; No advertising, no registration forms, nothing annoying
Limitations: .smi and .smil files only play the first part of a clip. This is only a problem when the clip consists of multiple parts. These files are not very common, and do play correctly when embedded in a browser. The RealMedia DirectShow splitter does not work with streaming content.