The two healthcare resources I find myself using most consistently on my ectopic brain (a.k.a. my PDA /Smart phone) are ePocrates and MedCalc. My earlier recommendations of these excellent portable memory expanders on the Palm and Windows Mobile operating systems still stands, with this addition.
If you are an iPhone or iTouch user the excellent characteristics of these programs shine on Apples portable systems.
http://med-ia.ch/medcalc/iphone_description.html
http://www.epocrates.com/index.html
