While there is a little bit of disappointment - the cards generally contain wood or fabric, and they're tiny - there's no denying the draw of these location-based relics.
So what is Topps to do next year?
2012 is the year of gold, as far as Topps is concerned, so I think it would be great to see "gold ore" cards, with little slivers of rock from gold rush sites across the world. There are 52 identified major gold rushes listed on this Wikipedia page, more than enough to contact some town leaders and ask for a couple rocks to be mailed to New York and make a full set out of. The cards could be die-cut to the shape of a gold bar or a gold nugget, embedded with a sliver of rock or a flake of gold, and numbered to 50.
How about a Shakespeare "relic" set, with pages from his works? One card for each major work, each card containing one full scene - owning a full serial numbered set would then give you a full Shakespearean play. Then you could also have one card for his sonnets, with each sonnet being its own serial number. There wouldn't be many cards for each work - Julius Caesar would be numbered to only 18! These could be cabinet-sized box toppers to be able to fit each scene on a card. (This idea could be carried over to a full authors series, of course.)
What about a tree relic set? Topps loves cutting up pieces of wood, so a card set die-cut in the shape of each tree type could be done.
Or carry over the flower card concept from the previous year and create cards embedded with full pressed flowers, similar to the Goodwin Champions entomology sets.
I'll be bringing more Allen & Ginter set ideas over the next few days, but what "relic" set would you like to see in next year's release?