I don't know about you guys, but my mum still has a massive pot of Sudocrem that I remember using when I had chicken pox at the age of six. A whopping twenty years later, testimony to its never going off, it still heals spots and helps smooth wounds even now - despite it technically going out of date in 1997.
Last year, I bought my own pot. I know, daring right? And since that time, I have used it on everything. Spots, burns, hangnails, cracked knuckles, blisters, shaving rash, you name it. It's such a household name that many people tend to forget or just take for granted this little (or rather, this big tub of) magic product. From the tiny dent I've made in the top of it, I'll definately still be using this in twenty years time.
For me, it's value comes under the header 'priceless'.