Profoot Care Slik Stik, Anti-Blister Stick is a fairly new product marketed as a "miracle" anti-blister stick. It generally lives up to its name!
The stick looks and feels quite a bit like a deodorant stick. Rub it on your feet where your shoes rub, and the product leaves a moisturizing barrier that helps prevent excessive rubbing and chaffing. The product goes on clear and has no scent that I could notice.
The anti-blister stick also works pretty well. I tried some on a pair of heels that I have been unable to wear for any length of time because the strap was rubbing too much. With use of the Profoot Slik Stik, I was able to actually wear the shoes. I still would not take a lengthy walk in them, but the stick allowed me to wear them to work for a day with no real problems. So it saved a pair of cute shoes that were otherwise destined for Goodwill.
Another similar product is Band-Aid Active Flex Blister Block Stick. I haven't tried the Band-aid product, but it appears to be essentially the same thing.