Take a look at this, from Palmball.com:
A Michigan couple went to inspect a leak in their basement. But instead of water damage, they found a stash of baseball tobacco cards hidden in the ceiling by the man’s grandfather. The cards were from 1910 and 1911.
Estimated worth? $50,000!
My dishwasher was leaking recently. I inspected the leak and discovered a mailer from Krispy Kreme. Estimated coupon value: $3.50
(Tip of the cap to Baseball Musings.)