Sure, biker patches look cool on your vest, but have you ever considered the possibility that one could save your life? On the Cheap Place's Biker Patches page I found these Blood Identity patches which could do just that - save your life. These are small, 4" x 2" patches that identify your blood type and have a small box at the bottom for your name. If you were ever in a serious accident, emergency responders would be able to tell your blood type from looking at the patch. What a great idea!
None of us likes to think about the fact that we could be in a traffic accident. And while that's normal, bikers need to be more concerned than car drivers because they are at a much larger risk for serious injury or death. An accident that would leave a car driver with a few bumps and bruises could be extremely serious for the biker. It seems that any small step a biker could take to significantly increase his chances of accident survival would be well worth it. In the case of these patches, I think $4 is a reasonable price for the added benefit.
All in all, blood identity patches are a great idea that should be taken advantage of by everyone who rides a motorcycle. Heaven forbid you have an accident. But if you do, one of these patches could very well be the most important one you ever purchased.