Doug Cannon's HP48 Page  
   HP48 calculator programs, programming tips, source code, and other information.
   http://www.geocities.com/doug_cannon

How To Open Your HP48  
   Illustrated instructions about how to open your HP48. Instructions by David Fenyes. Plus additional information.
   http://www.contrib.andrew.cmu.edu/~drury/how2open.htm

hpcalc.org  
   Premier website for program that run on the HP48, HP38 and HP28 series of calculators Formerly known as hp48.ml.org
   http://www.hpcalc.org/

Andr Schoorl's  
   HP48 calculator programs. The interests here are programs and related items for system RPL and assembly language programming as well as symbolic math.
   http://www.engr.uvic.ca/~aschoorl/

Meta-Kernel  
   The Meta Kernel is a kernel which enhances and accelerates many HP48 GX functions.
   http://www-miaif.lip6.fr/gerald/english/mk.html

ALG48 Library Page  
   Libraries on this site: ALG48, RSIM, and AIO48.
   http://homepages.msn.com/Terminus/cnfiechter/hp48/

Frequently Asked Questions About the HP49  
   Information about the HP49G, HP's latest calculator still in development.
   http://www.hpcalc.org/hp49/docs/faq/