PSA, PMS... one of those 3-letter acronyms

Q: Why do they call it PMS?
A: Because Mad Cow Disease was already taken.

Now that I've annoyed my cherished female visitors, on to the PSA...

Give blood. There is never enough blood on hand for emergencies, but they're desperate for donations right now. Our local blood bank has just 30 units of Type O in stock, and they average 400 units a day to local hospitals. Critical shortage. It doesn't hurt. It doesn't take that long either, so please help.

Do I practice what I preach? I used to. The American Red Cross has deemed me an unsuitable doner because I spent time in Europe during the mad cow crisis (see, there was a tie-in there). A significant percentage of doners in this area have been disqualified, which contributes to the ongoing shortage.