torrent,
sometimes the company behind it "rent out" the grid network to other projects (such as smallpox, anthrax research etc).
You can change your setting s to only do cancer research work units if you like - it will be in your project home page settings.
Even though my reason for doing it is Cancer Research, I tend to leave mine processing whatever units they send me as
a - these tend to be short lived campaigns
b - they bring money into the organisation who run it, and therefore help fund the cost of the cancer research
As long as you sign up on every PC with the same name, then the LOC team will get the points
as said read post...