I downloaded and installed graphing calculators for my Palm today.
Now I can choose between HP48SX, HP48GX and HP49G on my handheld

The website version of Power 48 does not run HP49G.
There is an update available here.
Calculator ROMS are available here.

Trying to learn about RPN from Wikipedia, I landed here.
Voidware, hpcalc.org and HP calculator museum were interesting too.