If you register for the Fit One HM, 10k, 5k today (June 4), the registration fee is only $15. I don't know if this is a barefoot friendly race, but looking at the course, a lot of it is on the greenbelt. I'll be doing the HM. http://www.fitoneboise.org/race
My husband is on the other side of the world until late Friday night. Unfortunately, I don't think a midnight trip to get him at the airport Friday is compatible with getting up for a race in the morning. Let me know how it goes!