Fingertip pulse oximeter
I've only used it once but it seems nice
The Applied Home Healthcare Fingertip Pulse Oximeter is ideal for use in multiple applications; hospital, nursing home, community medical treatment, home care, sports center, etc. This portable and non-invasive spot check will detect and measure oxygen saturation and heart rate. This pulse oximeter displays digital SpO2 and pulse rate while using bar graph technology to monitor heart rate.