Real Alternative plays RealMedia files without needing to install RealPlayer. It comes bundled with Media Player Classic, which includes support for all common RealMedia file formats including RM, RAM, RMVB, and the SMI and SMIL formats. The RealText (RT) and RealPix (RP) formats are also supported. The included RealMedia Browser plugin supports Internet Explorer, Opera, Netscape and Mozilla. Unlike RealPlayer, there are no registration reqs.
