Usually I hate it when classic costumes are redesigned. This piece by artist Dan Mora is a little different.
Daredevil, still in a red costume, but a little more practical than just a big red jumpsuit. You can see this working better in a TV show. DD has a collar, leather wrappings around his wrist / forearms, a cool belt, knee pads. Yet it still stays true to the roots of the Wally Wood costume. I like it a lot!
Spider-Man 2099. Here's one costume that I don't think should be changed, it's fantastic, and Marvel for some reason decided to change it to a white and blue monstrosity - to not confuse readers with Miles Morales? Hard to say. Mora does a great job capturing Spider-Man 2099 in a futuristic setting, and you can still see his costume even though the background buildings are colored with blue tones!
You can find more of Dan Mora on his Deviant Art page. Nuff Said!