 PRIMARY OBJECTIVES: I. To assess the clinical activity of timed administration of TMZ therapy in patients with stage IV melanoma who have or have not received prior chemotherapy for metastatic melanoma. SECONDARY OBJECTIVES: I. To assess the toxicity profile of timed administration of TMZ therapy in patients with stage IV melanoma who have or have not received prior chemotherapy for their metastatic disease. II. To evaluate the parameters of immune homeostasis that are associated with the anti-tumor immune biorhythm in order to gain insight into the mechanism of the observed clinical and immunological effect of timed TMZ chemotherapy. III. To evaluate the impact of timed TMZ chemotherapy on immune biomarkers and the anti-tumor immune biorhythms. OUTLINE: Prior to initiation of therapy patients will undergo a period of immunologic monitoring to analyze the bioperiodicity of their anti-tumor immune response. Patients with an established biorhythm will receive TMZ orally PO starting on the recommended day for 5 days. Treatment repeats every 21-42 days based on the established biorhythm until of disease progression or unacceptable toxicity. Patients without an established biorhythm are given the option to go off study or receive TMZ PO on days 1-5. Courses repeat every 28 days until disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up for up to 2 years. 