Our Nashville show was this weekend, and I made a couple of nice finds-- one from my own album that I had overlooked for a number of years. I posted a couple of these on VSC earlier tonight:
An illegal use cover-- the 1851's and 1857's were no longer allowed to be used after September of '61 due to the succession of the Southern states-- this one is dated 1867:

A nice #25, that was sold as a #26 for $4.00:

Jury is still out on this one-- I have not yet confirmed, but am hopeful that this one is a Type Va, not listed as a major Cat number in Scott, but where a Type V (24) is about $40 CV, the Type Va is shown as $250:

And the best was one I found in my own album! I've had it in the space for a 25 for about 10 years, and never noticed that both sides have an inner line-- making it a 25A, NOT 25 ($550 vs. $125):

Enjoy! Ray