It's no secret that death means virtually nothing in the DC/Marvel universes. When even Bucky and Jason Todd can stage comebacks, surely nobody can rest easy in the grave!
The reason for this, I think, is because the big two don't like to waste a trademarked character. And quite rightly so; just look at how much money the Blade trilogy of movies made, and is he even a B-list character? Theoretically, any hero or villain could be used to turn a profit, so they cling on to them like a super-glued limpet.
Fair enough, but as a reader it's starting to irrtate me: up against impossible odds, the hero bravely sacrifices his/herself, dies nobly - and then comes back. :( It devalues the story and makes the death look like a cheap shock tactic. Which it may well be in some cases, but that's beside the point.
Anyway, I was wondering if a compromise was possible: leave the character dead, but keep the trademark alive. After all, you'd only have to think up a way to have the hero/villain make a cameo appearance once in a while, and that should be good enough to retain control of 'em as an intellectual property. Still all good as far as merchandise and T.V./film rights go, yeah?
Then I realised that there were actually several ways to achieve this, listed below (inspired by the insightful posts of Lorendiac), and I was wondering if anyone could think of any more?
1) Clones! Yeah, I know, they suck, but cloning would provide a way to bring the costumed identity back, while leaving the original character dead.
I believe D.C. used this trick to bring back the Guardian in their Superman line in the 90's. Same powers, same appearance, stick them in the old outfit and away you go!
2) Parallel worlds! "This is Captain Supreme - but Captain Supreme from another world!!!" Even better than the clone, this 'copy' is absolutely identical, but the 'real world' version remains worm food! For example; the return of Proteus in Exiles.
3) The successor! See Lorendiac's post here. Wally West, Kyle Rayner, etc. Superheroics as a franchise!
4) Time Travel! Travel back in time to meet your hero (e.g. the new Mr Terrific meeting the original in J.S.A.), or better yet, bring them forward to meet you (see Hawkeye's time-travelling appearances in She-Hulk, or the return of you-know-who in Civil War: the Return)!
5) Hallucination! You feature the dearly departed in the story, but they're not really there! It's a vision, a day dream, a result of mind control, whatever. Wasn't there a story in which the Silver Surfer once had his conscience speak directly to him, in the form of the original Captain Marvel? I'm fuzzy on the details of that, admittedly.
6) The Flashback! The most simple option. The character features in an Untold Tale, set earlier in their career: Kurt Busiek's Untold Tales of Spiderman had Gwen Stacy running around, IIRC. May involve a dash of retcon, but it's still the easiest choice.