There is a plan afoot to climb Mt. Rainier this summer with GPS equipment and a gravitometer. Previous expeditions were made in 1988 and 1999, resulting in useful GPS data and lots of breathtaking pictures, which you may see in Larry Signani’s PowerPoint presentation (102mb download) at:
http://www.wss-acsm.org/MT-RAINIER-REMEASUREMENT.ppt
A PDF version (50mb download) of the same PowerPoint can now be found at: http://www.wss-acsm.org/MT-RAINIER-REMEASUREMENT.pdf
If you are interested in being a part of the climb effort, join http://groups.google.com/group/rainier-survey-2010.