This is a phase 1, open-label trial of perifosine and gemcitabine in patients with malignancies for whom single agent gemcitabine is a reasonable treatment option. All patients will receive gemcitabine at a dose of 1000 mg/m2 on days 1 and 8 of a 21-day cycle. Patients will receive perifosine orally at a dose of 50, 100 or 150 mg per day for the first 14 days of the 21-day cycle. Cohorts of 3 patients will be treated with doses of 50 mg administered either once, twice or three times a day. In this study a maximum tolerated dose (MTD) will be defined as a dose that can be given without grade 3/4 non-hematologic toxicity in more than 1/3 patients. If 2/3 patients in any cohort encounter a grade 3/4 non-hematologic toxicity, an additional 3 patients will be added. If the dose is intolerable for >3/6 patients then the previous level will be declared the MTD. Once an MTD has been determined an additional 10 patients will be added at the MTD to better define the expected toxicities.