It only counts if someone will actually pay for it, but the asking price for this ashcan edition of Flash #1 is a cool $5,000,000, plus $10 (Canadian) shipping. According to the listing, there are only six copies in existence of this particular comic, and this one is the highest grade (9.6). Of course, a good story helps to sell the product, and here it is:
In late 1939, DC and Fawcett, coveting this title, each raced to get its own ashcan version printed and a copyright secured. Each succeeded in printing an ashcan, but DC beat Fawcett to the punch, ever so barely, and gained the copyright to Flash Comics. The title became one of DC's mainstay Golden Age series, and, later, in 1956, the prime namesake character, The Flash, was instrumental in launching the Silver Age. This COMIC was acquired from long-time Golden Age DC Editor/Production Manager Sol Harrison, who was an excellent custodian of the rare copy.
If that's not enough to make you take out a second mortgage, then your nerd cred is due for a checkup.
Of course, the 5 mil is only the Buy It Now price; the seller will consider the best offer. Eli at Comic Attack, who found this listing, did a bit of research and determined that the comic had already been up for sale once, with a winning bid of US $4,950,990, but the sale didn't go through; apparently (amazingly) the would-be buyer had trouble coming up with the scratch. Or maybe they just woke up the next morning and came to their senses.