Had it happen to me for the 2nd time today. I was flying along at 25mph and bam - bee goes right in one of my vents. Fortunately, this time I was able to slam my brakes and pull the helmet soon enough, before I was stung. Last time, I wasn't so smart, and tried to pull my helmet off while riding. I wasn't stung, but my sunglasses were caught by my strap, and sent under my back tire.
The silver lining is it's spring time!