Microsoft's antitrust troubles in Europe reached a head last week when the company faced off against regulators and competitors in a Brussels, Belgium, courtroom and argued its case. Chief among the competitors is RealNetworks, creators of the RealOne media player. RealNetworks is asking the European Union (EU) to force Microsoft to remove its Windows Media Player (WMP) from Windows because it unfairly gives WMP an advantage over the product's competition. According to Microsoft, certain functions in Windows XP won't work if WMP is removed, but RealNetworks gave EU a demonstration that reportedly proved Microsoft wrong. (The hearings were closed to the public.) What's next? Will a TCP/IP provider ask the courts to force Microsoft to remove networking support from XP, too?