The latest datalogger I'm playing with is the LabPro by Vernier (http://www.vernier.com/). The logger/programmer is smart, it detects the sensors plugged into it. After collecting data, the programmer then processes the data appropriately for the sensor and displays the results in a chart. You can export your data into a text file for processing in a spreadsheet. That's great for incorporating GPS data. I'll post my notes on using the datalogger on my website alogn with some pictures on making a LabPro BalloonSat.
Vernier is popular in science classrooms.