Actually, Justice League International #1 and any of it’s imitators are fun. JL Europe #1, the Justice League Antarctica annual (where they are all looking the wrong way). I know there are more, but not being a big DC guy, I can’t name too many.
Here’s a site for DC comics that should complement the Marvel site listed above.
If you’re looking for images that are bold, legible and often ludicrous, it’s nigh-impossible to beat Silver and early Bronze Age comics covers. They’re exceedingly comic-booky, and were designed to jump out from a crowded newsstand and grab you by the visual short hairs. Plus a lot are still extremely affordable, especially if you’re not too picky about rolled spines and other flaws.
Ghost in the Shell #1’s cover is one of the most beautiful things I have ever seen and is one day in the near future going to be transferred permanently to my upper arm.
Most anything by Ross is a good bet. Especially the Kingdom Come series.
You could go here and find one you like then hunt it down.
Here’s a starter list (all comics are '60s versions, if there’s a question)
Flash #133 and #174
X-Men 50 or 58 (1969-ish)
Teen Titans #14
Justice League of America #22
Aquaman #37 or 42
Batman #194
Spider-Man #28
T.H.U.N.D.E.R. Agents #12
Fenris
Just about anything by Jim Steranko. His covers for Nick Fury, Agent of S.H.I.E.L.D. were particularly good, especially Issue 3 and Issue 7. Captain America #113 isn’t too shabby, either!
I’ve got some of Chris Ware’s Acme Novelty Library (No. 1 is my favorite) in frames. Here’s the do-it-yourself method that I used; a framing professional might give you better options, though.
They are triple matted, so there is a depth of about 3/8 of an inch between the glass and the back. (I think a double mat would be fine, too.) The opening of the mat is just a tiny bit larger than the dimensions of the comic. I put the comic in a plastic cover (I’d add a cardboard backing for a floppy comic), flattened it as taut as possible and taped it directly to the back of the mat with white artist’s tape. The comic is thus suspended, sort of shadow-box style, between the glass and backing. The triple mat adds a nice border to the cover. The plastic cover is not very noticeable under the glass, and it makes it easy to switch out the comics if you want to (white artist’s tape is removeable, too).
I second pretty much any Alex Ross cover. He does some amazing work. The “Kingdom Come” covers are especially good.
“Hellblazer” has some pretty awesome coveres for my money… especially Dave McKean’s original work early in the series, plus Glenn Fabry’s and Tim Bradstreet’s contributions later. Some of my favorites:
Hellblazer 65
Hellblazer 69
Hellblazer 81 (perhaps the best of the whole series)
Hellblazer 134
Hellblazer 139
I like R. Crumb’s Fritz the Cat, the one where he has his hand down the other cat’s shirt.
As a kid, I decorated my bedroom wall with comic books – hanging in poly-bags like the display at the store. Every inch was covered, which made for a colorful design (take that, “Trading Spaces”!). Sadly, off the top of my head, I can’t think of which were the better ones. Only one has been mentioned so far:
In fact, most of the covers on my wall were John Byrne, Walt Simonson, Alan Davis, Jim Lee, and the Art Adams covers from the X-Men reprints. Mike Mignola did some good-looking stuff, but I didn’t have much of it.
Covers started sucking when they changed from depicting scenes (whether they happen in the book or not) to simple dramatic poses.