 This treatment protocol allows doctors to treat advanced kidney cancer with an investigational drug called sorafenib, BAY43-9006, which is being studied in clinical trials for kidney cancer and other kinds of cancer. This treatment protocol is not a clinical trial in which sorafenib is compared to another equal treatment. All patients in this protocol will be treated with sorafenib. In addition, data from the patients who participate in this protocol will provide additional information about the drug. 