A famous autograph is only worth as much as someone else is willing to pay for it at a particular time.

But Reddit user TinCanGoat knows the individual signatures of comic book artists in a special collection put together by the redditor will always maintain the same minimum value: $1. That’s because TinCanGoat asked those artists to autograph and do a small sketch on American—and in some cases, Canadian—currency.

Recently, the Reddit user shared a gallery of the doodled-on dollars in the Comic Book community. The autographs were collected between 2014 and 2015 at Emerald City Comicon in Seattle, Rose City Comicon in Portland, Ore., and the Library Comic Con in Boise, Idaho.

TinCanGoat also explained how this practice began with a popular award-winning artist known for his work on Starman and Ex Machina.

Future artists, however, didn’t make Harris’ mistake and took extra time to use more than the Sharpies provided by TinCanGoat to render their money masterpieces. In fact, writer and artist Matt Kindt, who created MIND MGMT for Dark Horse and has worked on a variety of titles for DC, Marvel, and Valiant, scoured a convention for 15 minutes for a cigarette lighter, yelling, “Doesn’t anyone smoke anymore?” according to TinCanGoat.

Here’s a look at some of the other well-known artists TinCanGoat was able to convince to creatively deface legal tender for the sake of posterity.

Mark Bagley (Ultimate Spider-Man)

Joelle Jones (Lady Killer)

Frank Cho (Liberty Meadows, Totally Awesome Hulk)

Alex Maleev (Daredevil)

Jim Zub (Wayward)

Steve Lieber (Whiteout, Superior Foes of Spider-Man)

Check out the full gallery posted by TinCanGoat in the Comic Book community.