The 10usd TeleHealth Module

This low cost, multifunction peripheral will provide a means through which the XO can relay valuable medical diagnostic data from the field to doctors many kilometers away.
It will compose of a three lead EKG providing valuable information about the heart's electrical status, enabling diagnosis of congenital defects and various arrhythmias.
It will also contain a multipurpose NIR diagnosis tool whose primary function is that of a pulse oximeter, providing information about the oxygen saturation of the blood.
- See nirdiagnositics.com for other NIR functions

3 Lead EKG

Multiple Op-Amps pick up, amplify, and filter electrical impulses picked up by near-heart electrodes.
DyD/DyDisMe has schematics for an EKG using 714 style op-amps.

Based on the principles of the differences in absorption of oxygenated and non oxygenated hemoglobin
800-1000nm light from LEDs are often used in NIR tools
Red light is generated from similar LEDs.
- 10-20c per unit
Light is picked up by photodiodes, converted to current.
This current is amplified and converted to voltage by a MAX4006 or equivalent chip
- 1.275 usd

C8051F321 or equivalent chip
- A/D 5x10b minimum
- This specific chip provides A/D 13x10b
alternatively a USB micro-controller may communicate with dedicated ADC/DAC chips via PWM, to lower cost.

Some talk of a pictograph/text based diagnosis library/activity has been made.
User:DyD has collected some diagnosis aids used by a local hospital.
User:ZdenekBroz has been working on a wikislice of relevant medical information.
A very simple pygtk/xml based activity could be made using if/elseif clauses to mimic a diagnostic flowchart.
The biggest problem here is legal liability, a hefty disclaimer may be needed.