Milestone Prizes

I'm trying to think of things I could give myself as "prizes" for every 10 pound milestone. I've been wanting to go to a salon and get my hair highlighted, so I've decided I won't let myself until I've lost 10 pounds. But I can't think of what to do for 20, 30! I know 40 will be new clothes... but I don't wan to buy new clothes at the 20 and 30 mark because I wouldn't plan on them fitting very long anyways. I don't want to spend too much, as I'm also trying to get in control of my finances.
I'll have to think about this one! Maybe it will be more clear once I hit the 10 pound loss mark.