My region gives a ribbon for 5 pounds and then a gold paper star for every 5 pounds. Other regions do different things. My region does not give 25, 50, 75 or 100 pound rewards either. The only other things we get (I think) is the key chain and charms.
My leader is very careful about the awards. So far I've seen a bookmark for the first 5 and a star for every five after that, except for 25, which is a star magnet. There's also the key ring for 10%, and charms for 16 weeks, goal, and lifetime.
In addition to the above mentioned items, we have "bravo" stars. The leader hands these out for lifestyle changes, good suggestions, when someone just needs an extra pat on the back, etc.