Gillette Blue Blades

Just found a box of these at a local antique store. Picked 'em up for a couple of bucks.
What weird-but-cool looking blades. Are they even worth trying a shave (I usually use Feathers), or should these just be for show?

Oh please to god!!!!Just for show!!!!!! Nice catch though!!!!

I know everyone says you can't use these old blades because they're carbon steel and they rust etc. but has anyone actually tried shaving with an new-old blue blade? What happened?!
My neighbour says he has a little box that his grandfather used to use to sharpen razor blades - could something like that be used to make an old blue blade useable again?
Does someone else want to have a go?!