With the Amazing Heroes Kickstarter campaign having less than a day to go (they have yet to meet their goal), plus the recent solicitation email from GBJR Toys (that's everyone's favorite trolling toy "creator" Geoff Beckett's follow-up to Shocker Toys) that they are looking to fund the Spotlight Golden Age toy line via some place I will not link to (I don't want you to suffer the fate of 100s of other people still waiting on product or refunds)...just why are these Public Domain Super Heroes generating such a buzz?
The obvious reason is that you don't have to pay any licensing fees. So find some cool characters whose Copyright has run out or hasn't been renewed...and make a toy out of them. You don't have to get into negotiations with Marvel or DC, which means you don't have to fork over a good portion of the profits.
But if something sounds too good to be true...it likely is. It's not as if Superman - or even Aquaman - are in the public domain. Most "good" public domain characters comes from the literary world. Think of the assemblance of characters in The League of Extraordinary Gentlemen or Showtime's new series Penny Dreadful. Both make use of well-known character now in the public domain.
There are a handful of interesting super heroes, but they're almost entirely included in the Amazing Heroes line. A lot of the characters in the public domain are just unimaginative or don't have a place in modern culture. Lots of blatant racism back in the 1940's...
There's a great informational database at pdsh.wikia.com. They have information and photos (some of the ones I stole here...I'm assuming they're public domain as well) on several thousand Public Domain Super Heroes.