tinyE: The Sega Genesis Gold CD Rom has a few good ones (most notably Streets of Rage 1 & 2) I picked up the rom but I'm pretty sure Steam has all of them, if you are that desperate. :P
Yea, I got that for my Xbox 360 and it's awesome. I'd really like to see a modern take on beat 'em ups because we've got technology and resources to make this genre very deep and advanced while still keeping that core of smashing someone's a$$.
I'm really glad for all the remakes that come out for consoles and PC, I truly am, but pushing it further into what we can do now would be great too. On Steam you can get a couple of the overhead racing games which I enjoy, too. Beat 'em ups shouldn't be that far behind