Why? Do you really need a reason? Well, in this case, it may a useful activity. There's a new chip available that can be used by mobile devices to diagnose sexually transmitted diseases:
Link via Gizmodo | Photo (unrelated) via Flickr user Jacky Cheong used under Creative Commons license
People who suspect they have been infected will be able to put urine or saliva on to a computer chip about the size of a USB chip, plug it into their phone or computer and receive a diagnosis within minutes, telling them which, if any, sexually transmitted infection (STI) they have. Seven funders, including the Medical Research Council, have put £4m into developing the technology via a forum called the UK Clinical Research Collaboration.
Link via Gizmodo | Photo (unrelated) via Flickr user Jacky Cheong used under Creative Commons license
Seriously, tho. Cell phones can do everything else. Why not add to the list?