The sticker is made of high quality vinyl and leaves no residue should you decide to remove it. At US$18, it's a little pricey, but for DC comic book lovers, this is a must have!
Thanks to TUAW reader John for the tip!
UPDATE: The creator of this decal (who had no idea I was going to write about it) just sent me an email. He is offering all TUAW readers 15% off the JLA decal as a thank you to TUAW readers for making his Iron Man decal a best seller after appearing on this site. Just enter "TUAW" on check out (will only work with Google checkout at this time, darn Paypal!) to get your 15% off! Sweet!