Ultra Marathon? Anyone?

I've been researching ultra marathons...

When I went to pick up my packet the day before my race (North Face Endurance Challenge at Bear Mountain - Half Marathon) a lot of the 50 milers were coming in, along with the marathoners, 50k, and Marathon relay participants. They do the longer events on Saturday and the Half, 10K and 5K on Sunday. I was mesmerized by the 50 milers.

All participants receive a red technical shirt, you then head over to the shirt screening tent and tell them which event you've done or are going to do and they screen it for you. I was on line with a couple of 50 milers and yes I was staring in awe at the attractive but otherwise normal looking 30 something year old man and woman and I stupidly asked with the slightest tone of incredulity, "you just ran 50 miles?" They looked over at me, shrugged their shoulders and nonchalantly, said, "yeah". Well, I was impressed, as were my 13 y.o. son and his good buddy who came up with me.

Days later I'm still in awe and now I'm contemplating running that race next year.